From 2dcbe101b49dd942adbc78e61bf8011d3e8e1d5c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Diego=20Elio=20Petten=C3=B2?= <flameeyes@flameeyes.eu>
Date: Wed, 12 Dec 2018 22:53:49 +0000
Subject: Fix most of the pylint output, and hide away some that is not needed.

Again, this is not ready for CI yet unfortunately :(
---
 .pylintrc                                          |  12 +++
 glucometerutils/common.py                          |   9 +-
 glucometerutils/drivers/accuchek_reports.py        |  57 +++++++-----
 glucometerutils/drivers/fsinsulinx.py              |   2 +-
 glucometerutils/drivers/fslibre.py                 |   2 +-
 glucometerutils/drivers/fsoptium.py                | 101 +++++++++++----------
 glucometerutils/drivers/fsprecisionneo.py          |  10 +-
 glucometerutils/drivers/otultra2.py                | 100 ++++++++++----------
 glucometerutils/drivers/otverio2015.py             |   6 +-
 glucometerutils/drivers/otverioiq.py               |   2 +-
 glucometerutils/drivers/sdcodefree.py              |  21 +++--
 glucometerutils/glucometer.py                      |  57 ++++++------
 glucometerutils/support/freestyle.py               |   5 +-
 glucometerutils/support/hiddevice.py               |  10 +-
 glucometerutils/support/lifescan.py                |  12 ++-
 .../support/lifescan_binary_protocol.py            |  20 ++--
 glucometerutils/support/serial.py                  |   4 +-
 17 files changed, 228 insertions(+), 202 deletions(-)
 create mode 100644 .pylintrc

diff --git a/.pylintrc b/.pylintrc
new file mode 100644
index 0000000..34485a1
--- /dev/null
+++ b/.pylintrc
@@ -0,0 +1,12 @@
+[MESSAGE CONTROL]
+disable=
+	duplicate-code,
+	too-few-public-methods,
+	too-many-branches,
+	too-many-locals,
+	too-many-nested-blocks,
+	too-many-return-statements,
+	too-many-statements,
+
+[BASIC]
+good-names = i, j, k, e, _
diff --git a/glucometerutils/common.py b/glucometerutils/common.py
index 8ffa724..7d7f0db 100644
--- a/glucometerutils/common.py
+++ b/glucometerutils/common.py
@@ -6,20 +6,17 @@ __email__ = 'flameeyes@flameeyes.eu'
 __copyright__ = 'Copyright © 2013, Diego Elio Pettenò'
 __license__ = 'MIT'
 
-import collections
 import datetime
 import enum
 import textwrap
 
 try:
     from typing import Sequence, Text
-except:
+except ImportError:
     pass
 
 import attr
 
-from glucometerutils import exceptions
-
 class Unit(enum.Enum):
     MG_DL = 'mg/dL'
     MMOL_L = 'mmol/L'
@@ -56,8 +53,8 @@ def convert_glucose_unit(value, from_unit, to_unit):
 
     if from_unit == Unit.MG_DL:
         return round(value / 18.0, 2)
-    else:
-        return round(value * 18.0, 0)
+
+    return round(value * 18.0, 0)
 
 @attr.s
 class GlucoseReading:
diff --git a/glucometerutils/drivers/accuchek_reports.py b/glucometerutils/drivers/accuchek_reports.py
index 49c698d..a29f0c6 100644
--- a/glucometerutils/drivers/accuchek_reports.py
+++ b/glucometerutils/drivers/accuchek_reports.py
@@ -26,8 +26,8 @@ from glucometerutils import common
 from glucometerutils import exceptions
 
 _UNIT_MAP = {
-  'mmol/l': common.Unit.MMOL_L,
-  'mg/dl': common.Unit.MG_DL,
+    'mmol/l': common.Unit.MMOL_L,
+    'mg/dl': common.Unit.MG_DL,
 }
 
 _DATE_CSV_KEY = 'Date'
@@ -47,17 +47,18 @@ _TIME_FORMAT = '%H:%M'
 
 _DATETIME_FORMAT = ' '.join((_DATE_FORMAT, _TIME_FORMAT))
 
-class Device(object):
+class Device:
     def __init__(self, device):
         if not device or not os.path.isdir(device):
             raise exceptions.CommandLineError(
-              '--device parameter is required, should point to mount path for the '
-              'meter.')
+                '--device parameter is required, should point to mount path '
+                'for the meter.')
 
-        report_files = glob.glob(os.path.join(device, '*', 'Reports', '*.csv'))
+        reports_path = os.path.join(device, '*', 'Reports', '*.csv')
+        report_files = glob.glob(reports_path)
         if not report_files:
             raise exceptions.ConnectionFailed(
-              'No report file found in path "%s".' % reports_path)
+                'No report file found in path "%s".' % reports_path)
 
         self.report_file = report_files[0]
 
@@ -68,23 +69,28 @@ class Device(object):
         next(self.report)
 
         return csv.DictReader(
-          self.report, delimiter=';', skipinitialspace=True, quoting=csv.QUOTE_NONE)
+            self.report,
+            delimiter=';',
+            skipinitialspace=True,
+            quoting=csv.QUOTE_NONE)
 
     def connect(self):
-        self.report = open(self.report_file, 'r', newline='\r\n', encoding='utf-8')
+        self.report = open(
+            self.report_file, 'r', newline='\r\n', encoding='utf-8')
 
     def disconnect(self):
         self.report.close()
 
     def get_meter_info(self):
         return common.MeterInfo(
-          '%s glucometer' % self.get_model(),
-          serial_number=self.get_serial_number(),
-          native_unit=self.get_glucose_unit())
+            '%s glucometer' % self.get_model(),
+            serial_number=self.get_serial_number(),
+            native_unit=self.get_glucose_unit())
 
     def get_model(self):
         # $device/MODEL/Reports/*.csv
-        return os.path.basename(os.path.dirname(os.path.dirname(self.report_file)))
+        return os.path.basename(
+            os.path.dirname(os.path.dirname(self.report_file)))
 
     def get_serial_number(self):
         self.report.seek(0)
@@ -99,23 +105,24 @@ class Device(object):
         return _UNIT_MAP[record[_UNIT_CSV_KEY]]
 
     def get_datetime(self):
-        raise NotImplemented
+        raise NotImplementedError
 
     def set_datetime(self, date=None):
-        raise NotImplemented
+        raise NotImplementedError
 
     def zero_log(self):
-        raise NotImplemented
+        raise NotImplementedError
 
-    def _extract_datetime(self, record):
+    def _extract_datetime(self, record):  # pylint: disable=no-self-use
         # Date and time are in separate column, but we want to parse them
         # together.
         date_and_time = ' '.join((record[_DATE_CSV_KEY], record[_TIME_CSV_KEY]))
         return datetime.datetime.strptime(date_and_time, _DATETIME_FORMAT)
 
-    def _extract_meal(self, record):
+    def _extract_meal(self, record):  # pylint: disable=no-self-use
         if record[_AFTER_MEAL_CSV_KEY] and record[_BEFORE_MEAL_CSV_KEY]:
-            raise InvalidResponse('Reading cannot be before and after meal.')
+            raise exceptions.InvalidResponse(
+                'Reading cannot be before and after meal.')
         elif record[_AFTER_MEAL_CSV_KEY]:
             return common.Meal.AFTER
         elif record[_BEFORE_MEAL_CSV_KEY]:
@@ -129,9 +136,9 @@ class Device(object):
                 continue
 
             yield common.GlucoseReading(
-              self._extract_datetime(record),
-              common.convert_glucose_unit(
-                float(record[_RESULT_CSV_KEY]),
-                _UNIT_MAP[record[_UNIT_CSV_KEY]],
-                common.Unit.MG_DL),
-              meal=self._extract_meal(record))
+                self._extract_datetime(record),
+                common.convert_glucose_unit(
+                    float(record[_RESULT_CSV_KEY]),
+                    _UNIT_MAP[record[_UNIT_CSV_KEY]],
+                    common.Unit.MG_DL),
+                meal=self._extract_meal(record))
diff --git a/glucometerutils/drivers/fsinsulinx.py b/glucometerutils/drivers/fsinsulinx.py
index 15bc131..fbde9ba 100644
--- a/glucometerutils/drivers/fsinsulinx.py
+++ b/glucometerutils/drivers/fsinsulinx.py
@@ -55,7 +55,7 @@ class Device(freestyle.FreeStyleHidDevice):
                 'Software version: ' + self._get_version(),),
             native_unit=self.get_glucose_unit())
 
-    def get_glucose_unit(self):
+    def get_glucose_unit(self):  # pylint: disable=no-self-use
         """Returns the glucose unit of the device."""
         return common.Unit.MG_DL
 
diff --git a/glucometerutils/drivers/fslibre.py b/glucometerutils/drivers/fslibre.py
index 6e3988c..5341573 100644
--- a/glucometerutils/drivers/fslibre.py
+++ b/glucometerutils/drivers/fslibre.py
@@ -205,7 +205,7 @@ class Device(freestyle.FreeStyleHidDevice):
         """Overridden function as the command is not compatible."""
         return self._send_text_command(b'$sn?').rstrip('\r\n')
 
-    def get_glucose_unit(self):
+    def get_glucose_unit(self):  # pylint: disable=no-self-use
         """Returns the glucose unit of the device."""
         # TODO(Flameeyes): figure out how to identify the actual unit on the
         # device.
diff --git a/glucometerutils/drivers/fsoptium.py b/glucometerutils/drivers/fsoptium.py
index 395494c..618fffa 100644
--- a/glucometerutils/drivers/fsoptium.py
+++ b/glucometerutils/drivers/fsoptium.py
@@ -29,8 +29,8 @@ from glucometerutils.support import serial
 
 
 _CLOCK_RE = re.compile(
-  r'^Clock:\t(?P<month>[A-Z][a-z]{2})  (?P<day>[0-9]{2}) (?P<year>[0-9]{4})\t'
-  r'(?P<time>[0-9]{2}:[0-9]{2}:[0-9]{2})$')
+    r'^Clock:\t(?P<month>[A-Z][a-z]{2})  (?P<day>[0-9]{2}) (?P<year>[0-9]{4})\t'
+    r'(?P<time>[0-9]{2}:[0-9]{2}:[0-9]{2})$')
 
 # The reading can be HI (padded to three-characters by a space) if the value was
 # over what the meter was supposed to read. Unlike the "Clock:" line, the months
@@ -38,29 +38,33 @@ _CLOCK_RE = re.compile(
 # characters, so accept a space or 'e'/'y' at the end of the month name. Also,
 # the time does *not* include seconds.
 _READING_RE = re.compile(
-  r'^(?P<reading>HI |[0-9]{3})  (?P<month>[A-Z][a-z]{2})[ ey] (?P<day>[0-9]{2}) '
-  r'(?P<year>[0-9]{4}) (?P<time>[0-9]{2}:[0-9]{2}) (?P<type>[GK]) 0x00$')
+    r'^(?P<reading>HI |[0-9]{3})  '
+    r'(?P<month>[A-Z][a-z]{2})[ ey] '
+    r'(?P<day>[0-9]{2}) '
+    r'(?P<year>[0-9]{4}) '
+    r'(?P<time>[0-9]{2}:[0-9]{2}) '
+    r'(?P<type>[GK]) 0x00$')
 
 _CHECKSUM_RE = re.compile(
-  r'^(?P<checksum>0x[0-9A-F]{4})  END$')
+    r'^(?P<checksum>0x[0-9A-F]{4})  END$')
 
 # There are two date format used by the device. One uses three-letters month
 # names, and that's easy enough. The other uses three-letters month names,
 # except for (at least) July. So ignore the fourth character.
 # explicit mapping. Note that the mapping *requires* a trailing whitespace.
 _MONTH_MATCHES = {
-  'Jan': 1,
-  'Feb': 2,
-  'Mar': 3,
-  'Apr': 4,
-  'May': 5,
-  'Jun': 6,
-  'Jul': 7,
-  'Aug': 8,
-  'Sep': 9,
-  'Oct': 10,
-  'Nov': 11,
-  'Dec': 12
+    'Jan': 1,
+    'Feb': 2,
+    'Mar': 3,
+    'Apr': 4,
+    'May': 5,
+    'Jun': 6,
+    'Jul': 7,
+    'Aug': 8,
+    'Sep': 9,
+    'Oct': 10,
+    'Nov': 11,
+    'Dec': 12
 }
 
 
@@ -99,8 +103,8 @@ class Device(serial.SerialDevice):
 
         logging.debug('Received response: %r', response)
 
-        # We always want to decode the output, and remove stray \r\n. Any failure in
-        # decoding means the output is invalid anyway.
+        # We always want to decode the output, and remove stray \r\n. Any
+        # failure in decoding means the output is invalid anyway.
         decoded_response = [line.decode('ascii').rstrip('\r\n')
                             for line in response]
         return decoded_response
@@ -109,7 +113,7 @@ class Device(serial.SerialDevice):
         self._send_command('xmem') # ignore output this time
         self._fetch_device_information()
 
-    def disconnect(self):
+    def disconnect(self):  # pylint: disable=no-self-use
         return
 
     def _fetch_device_information(self):
@@ -126,13 +130,13 @@ class Device(serial.SerialDevice):
                     self.device_glucose_unit_ = common.Unit.MMOL_L
                 else:  # I only have a mmol/l device, so I can't be sure.
                     self.device_glucose_unit_ = common.Unit.MG_DL
-            # There are more entries: Clock, Market, ROM and Usage, but we don't care
-            # for those here.
+            # There are more entries: Clock, Market, ROM and Usage, but we don't
+            # care for those here.
             elif parsed_line[0] == 'CMD OK':
                 return
 
-        # I have not figured out why this happens, but sometimes it's echoing back
-        # the commands and not replying to them.
+        # I have not figured out why this happens, but sometimes it's echoing
+        # back the commands and not replying to them.
         raise exceptions.ConnectionFailed()
 
     def get_meter_info(self):
@@ -142,11 +146,11 @@ class Device(serial.SerialDevice):
           A common.MeterInfo object.
         """
         return common.MeterInfo(
-          'Freestyle Optium glucometer',
-          serial_number=self.get_serial_number(),
-          version_info=(
-            'Software version: ' + self.get_version(),),
-          native_unit=self.get_glucose_unit())
+            'Freestyle Optium glucometer',
+            serial_number=self.get_serial_number(),
+            version_info=(
+                'Software version: ' + self.get_version(),),
+            native_unit=self.get_glucose_unit())
 
     def get_version(self):
         """Returns an identifier of the firmware version of the glucometer.
@@ -208,11 +212,6 @@ class Device(serial.SerialDevice):
         return self.get_datetime()
 
     def zero_log(self):
-        """Zeros out the data log of the device.
-
-        This function will clear the memory of the device deleting all the readings
-        in an irrecoverable way.
-        """
         raise NotImplementedError
 
     def get_readings(self):
@@ -221,19 +220,20 @@ class Device(serial.SerialDevice):
         Args:
           unit: The glucose unit to use for the output.
 
-        Yields:
-          A tuple (date, value) of the readings in the glucometer. The value is a
-          floating point in the unit specified; if no unit is specified, the default
-          unit in the glucometer will be used.
+        Yields: A tuple (date, value) of the readings in the glucometer. The
+          value is a floating point in the unit specified; if no unit is
+          specified, the default unit in the glucometer will be used.
 
         Raises:
-          exceptions.InvalidResponse: if the response does not match what expected.
+          exceptions.InvalidResponse: if the response does not match what '
+          expected.
+
         """
         data = self._send_command('xmem')
 
-        # The first line is empty, the second is the serial number, the third the
-        # version, the fourth the current time, and the fifth the record count.. The
-        # last line has a checksum and the end.
+        # The first line is empty, the second is the serial number, the third
+        # the version, the fourth the current time, and the fifth the record
+        # count.. The last line has a checksum and the end.
         count = int(data[4])
         if count != (len(data) - 6):
             raise exceptions.InvalidResponse('\n'.join(data))
@@ -244,12 +244,14 @@ class Device(serial.SerialDevice):
             raise exceptions.InvalidResponse('\n'.join(data))
 
         expected_checksum = int(checksum_match.group('checksum'), 16)
-        # exclude the last line in the checksum calculation, as that's the checksum
-        # itself. The final \r\n is added separately.
-        calculated_checksum = sum(ord(c) for c in '\r\n'.join(data[:-1])) + 0xd + 0xa
+        # exclude the last line in the checksum calculation, as that's the
+        # checksum itself. The final \r\n is added separately.
+        calculated_checksum = sum(
+            ord(c) for c in '\r\n'.join(data[:-1])) + 0xd + 0xa
 
         if expected_checksum != calculated_checksum:
-            raise exceptions.InvalidChecksum(expected_checksum, calculated_checksum)
+            raise exceptions.InvalidChecksum(
+                expected_checksum, calculated_checksum)
 
         for line in data[5:-1]:
             match = _READING_RE.match(line)
@@ -257,7 +259,8 @@ class Device(serial.SerialDevice):
                 raise exceptions.InvalidResponse(line)
 
             if match.group('type') != 'G':
-                logging.warning('Non-glucose readings are not supported, ignoring.')
+                logging.warning(
+                    'Non-glucose readings are not supported, ignoring.')
                 continue
 
             if match.group('reading') == 'HI ':
@@ -273,6 +276,6 @@ class Device(serial.SerialDevice):
 
             timestamp = datetime.datetime(year, month, day, hour, minute)
 
-            # The reading, if present, is always in mg/dL even if the glucometer is
-            # set to mmol/L.
+            # The reading, if present, is always in mg/dL even if the glucometer
+            # is set to mmol/L.
             yield common.GlucoseReading(timestamp, value)
diff --git a/glucometerutils/drivers/fsprecisionneo.py b/glucometerutils/drivers/fsprecisionneo.py
index 1153908..87076c2 100644
--- a/glucometerutils/drivers/fsprecisionneo.py
+++ b/glucometerutils/drivers/fsprecisionneo.py
@@ -64,7 +64,7 @@ class Device(freestyle.FreeStyleHidDevice):
                 'Software version: ' + self._get_version(),),
             native_unit=self.get_glucose_unit())
 
-    def get_glucose_unit(self):
+    def get_glucose_unit(self):  # pylint: disable=no-self-use
         """Returns the glucose unit of the device."""
         return common.Unit.MG_DL
 
@@ -82,10 +82,10 @@ class Device(freestyle.FreeStyleHidDevice):
             # Build a _reading object by parsing each of the entries in the raw
             # record
             values = []
-            for v in record:
-                if v == "HI":
-                    v = float("inf")
-                values.append(int(v))
+            for value in record:
+                if value == "HI":
+                    value = float("inf")
+                values.append(int(value))
             raw_reading = _NeoReading._make(values[:len(_NeoReading._fields)])
 
             timestamp = datetime.datetime(
diff --git a/glucometerutils/drivers/otultra2.py b/glucometerutils/drivers/otultra2.py
index a27d333..f26fc45 100644
--- a/glucometerutils/drivers/otultra2.py
+++ b/glucometerutils/drivers/otultra2.py
@@ -17,7 +17,6 @@ __copyright__ = 'Copyright © 2013-2017, Diego Elio Pettenò'
 __license__ = 'MIT'
 
 import datetime
-import logging
 import re
 
 from glucometerutils import common
@@ -27,32 +26,32 @@ from glucometerutils.support import serial
 
 # The following two hashes are taken directly from LifeScan's documentation
 _MEAL_CODES = {
-  'N': common.Meal.NONE,
-  'B': common.Meal.BEFORE,
-  'A': common.Meal.AFTER,
+    'N': common.Meal.NONE,
+    'B': common.Meal.BEFORE,
+    'A': common.Meal.AFTER,
 }
 
 _COMMENT_CODES = {
-  '00': '',  # would be 'No Comment'
-  '01': 'Not Enough Food',
-  '02': 'Too Much Food',
-  '03': 'Mild Exercise',
-  '04': 'Hard Exercise',
-  '05': 'Medication',
-  '06': 'Stress',
-  '07': 'Illness',
-  '08': 'Feel Hypo',
-  '09': 'Menses',
-  '10': 'Vacation',
-  '11': 'Other',
+    '00': '',  # would be 'No Comment'
+    '01': 'Not Enough Food',
+    '02': 'Too Much Food',
+    '03': 'Mild Exercise',
+    '04': 'Hard Exercise',
+    '05': 'Medication',
+    '06': 'Stress',
+    '07': 'Illness',
+    '08': 'Feel Hypo',
+    '09': 'Menses',
+    '10': 'Vacation',
+    '11': 'Other',
 }
 
 _DUMP_HEADER_RE = re.compile(
-  r'P ([0-9]{3}),"[0-9A-Z]{9}","(?:MG/DL |MMOL/L)"')
+    r'P ([0-9]{3}),"[0-9A-Z]{9}","(?:MG/DL |MMOL/L)"')
 _DUMP_LINE_RE = re.compile(
-  r'P (?P<datetime>"[A-Z]{3}","[0-9/]{8}","[0-9:]{8}   "),'
-  r'"(?P<control>[C ]) (?P<value>[0-9]{3})(?P<parityerror>[\? ])",'
-  r'"(?P<meal>[NBA])","(?P<comment>0[0-9]|1[01])", 00')
+    r'P (?P<datetime>"[A-Z]{3}","[0-9/]{8}","[0-9:]{8}   "),'
+    r'"(?P<control>[C ]) (?P<value>[0-9]{3})(?P<parityerror>[\? ])",'
+    r'"(?P<meal>[NBA])","(?P<comment>0[0-9]|1[01])", 00')
 
 _RESPONSE_MATCH = re.compile(r'^(.+) ([0-9A-F]{4})\r$')
 
@@ -94,7 +93,7 @@ def _validate_and_strip_checksum(line):
     try:
         checksum_given = int(checksum_string, 16)
         checksum_calculated = _calculate_checksum(
-          bytes(response, 'ascii'))
+            bytes(response, 'ascii'))
 
         if checksum_given != checksum_calculated:
             raise exceptions.InvalidChecksum(checksum_given,
@@ -105,7 +104,8 @@ def _validate_and_strip_checksum(line):
     return response
 
 _DATETIME_RE = re.compile(
-  r'^"[A-Z]{3}","([0-9]{2}/[0-9]{2}/[0-9]{2})","([0-9]{2}:[0-9]{2}:[0-9]{2})   "$')
+    r'^"[A-Z]{3}",'
+    r'"([0-9]{2}/[0-9]{2}/[0-9]{2})","([0-9]{2}:[0-9]{2}:[0-9]{2})   "$')
 
 
 def _parse_datetime(response):
@@ -136,10 +136,10 @@ class Device(serial.SerialDevice):
     BAUDRATE = 9600
     DEFAULT_CABLE_ID = '067b:2303'  # Generic PL2303 cable.
 
-    def connect(self):
+    def connect(self):  # pylint: disable=no-self-use
         return
 
-    def disconnect(self):
+    def disconnect(self):  # pylint: disable=no-self-use
         return
 
     def _send_command(self, cmd):
@@ -159,7 +159,8 @@ class Device(serial.SerialDevice):
           cmd: command and parameters to send (without newline)
 
         Returns:
-          A single line of text that the glucometer responds, without the checksum.
+          A single line of text that the glucometer responds, without the
+          checksum.
         """
         self._send_command(cmd)
 
@@ -173,11 +174,11 @@ class Device(serial.SerialDevice):
           A common.MeterInfo object.
         """
         return common.MeterInfo(
-          'OneTouch Ultra 2 glucometer',
-          serial_number=self.get_serial_number(),
-          version_info=(
-            'Software version: ' + self.get_version(),),
-          native_unit=self.get_glucose_unit())
+            'OneTouch Ultra 2 glucometer',
+            serial_number=self.get_serial_number(),
+            version_info=(
+                'Software version: ' + self.get_version(),),
+            native_unit=self.get_glucose_unit())
 
     def get_version(self):
         """Returns an identifier of the firmware version of the glucometer.
@@ -215,8 +216,8 @@ class Device(serial.SerialDevice):
 
         serial_number = match.group(1)
 
-        # 'Y' at the far right of the serial number is the indication of a OneTouch
-        # Ultra2 device, as per specs.
+        # 'Y' at the far right of the serial number is the indication of a
+        # OneTouch Ultra2 device, as per specs.
         if serial_number[-1] != 'Y':
             raise lifescan.InvalidSerialNumber(serial_number)
 
@@ -242,15 +243,15 @@ class Device(serial.SerialDevice):
           A datetime object built according to the returned response.
         """
         response = self._send_oneliner_command(
-          'DMT' + date.strftime('%m/%d/%y %H:%M:%S'))
+            'DMT' + date.strftime('%m/%d/%y %H:%M:%S'))
 
         return _parse_datetime(response[2:])
 
     def zero_log(self):
         """Zeros out the data log of the device.
 
-        This function will clear the memory of the device deleting all the readings
-        in an irrecoverable way.
+        This function will clear the memory of the device deleting all the
+        readings in an irrecoverable way.
         """
         response = self._send_oneliner_command('DMZ')
         if response != 'Z':
@@ -268,10 +269,10 @@ class Device(serial.SerialDevice):
         Raises:
           exceptions.InvalidGlucoseUnit: if the unit is not recognized
 
-        OneTouch meters will always dump data in mg/dL because that's their internal
-        storage. They will then provide a separate method to read the unit used for
-        display. This is not settable by the user in all modern meters.
-
+        OneTouch meters will always dump data in mg/dL because that's their
+        internal storage. They will then provide a separate method to read the
+        unit used for display. This is not settable by the user in all modern
+        meters.
         """
         response = self._send_oneliner_command('DMSU?')
 
@@ -280,10 +281,11 @@ class Device(serial.SerialDevice):
 
         if unit == 'MG/DL ':
             return common.Unit.MG_DL
-        elif unit == 'MMOL/L':
+
+        if unit == 'MMOL/L':
             return common.Unit.MMOL_L
-        else:
-            raise exceptions.InvalidGlucoseUnit(string)
+
+        raise exceptions.InvalidGlucoseUnit(response)
 
     def get_readings(self):
         """Iterates over the reading values stored in the glucometer.
@@ -292,12 +294,12 @@ class Device(serial.SerialDevice):
           unit: The glucose unit to use for the output.
 
         Yields:
-          A tuple (date, value) of the readings in the glucometer. The value is a
-          floating point in the unit specified; if no unit is specified, the default
-          unit in the glucometer will be used.
+          A GlucoseReading object representing the read value.
 
         Raises:
-          exceptions.InvalidResponse: if the response does not match what expected.
+          exceptions.InvalidResponse: if the response does not match what
+          expected.
+
         """
         self._send_command('DMP')
         data = self.serial_.readlines()
@@ -323,7 +325,7 @@ class Device(serial.SerialDevice):
             meal = _MEAL_CODES[line_data['meal']]
             comment = _COMMENT_CODES[line_data['comment']]
 
-            # OneTouch2 always returns the data in mg/dL even if the glucometer is set
-            # to mmol/L, so there is no conversion required.
+            # OneTouch2 always returns the data in mg/dL even if the glucometer
+            # is set to mmol/L, so there is no conversion required.
             yield common.GlucoseReading(
-              date, float(line_data['value']), meal=meal, comment=comment)
+                date, float(line_data['value']), meal=meal, comment=comment)
diff --git a/glucometerutils/drivers/otverio2015.py b/glucometerutils/drivers/otverio2015.py
index efd4114..3a73e20 100644
--- a/glucometerutils/drivers/otverio2015.py
+++ b/glucometerutils/drivers/otverio2015.py
@@ -43,7 +43,7 @@ _REGISTER_SIZE = 512
 
 _PACKET = construct.Padded(
     _REGISTER_SIZE,
-        lifescan_binary_protocol.LifeScanPacket(False))
+    lifescan_binary_protocol.LifeScanPacket(False))
 
 _COMMAND_SUCCESS = construct.Const(b'\x03\x06')
 
@@ -115,7 +115,7 @@ _READ_RECORD_RESPONSE = construct.Struct(
     construct.Padding(4),
 )
 
-class Device(object):
+class Device:
     def __init__(self, device):
         if not device:
             raise exceptions.CommandLineError(
@@ -135,7 +135,7 @@ class Device(object):
             raise exceptions.ConnectionFailed(
                 'Device %s is not a LifeScan glucometer.' % self.device_name_)
 
-    def disconnect(self):
+    def disconnect(self):  # pylint: disable=no-self-use
         return
 
     def _send_request(self, lba, request_format, request_obj, response_format):
diff --git a/glucometerutils/drivers/otverioiq.py b/glucometerutils/drivers/otverioiq.py
index deafed4..67781a7 100644
--- a/glucometerutils/drivers/otverioiq.py
+++ b/glucometerutils/drivers/otverioiq.py
@@ -176,7 +176,7 @@ class Device(serial.SerialDevice):
         return response.timestamp
 
     def set_datetime(self, date=datetime.datetime.now()):
-        response = self._send_request(
+        self._send_request(
             _WRITE_RTC_REQUEST, {
                 'timestamp': date,
             }, _COMMAND_SUCCESS)
diff --git a/glucometerutils/drivers/sdcodefree.py b/glucometerutils/drivers/sdcodefree.py
index 1eba6e6..8e7b29c 100644
--- a/glucometerutils/drivers/sdcodefree.py
+++ b/glucometerutils/drivers/sdcodefree.py
@@ -139,7 +139,7 @@ class Device(serial.SerialDevice):
         logging.debug('sending packet: %s', binascii.hexlify(pkt))
         self.serial_.write(pkt)
 
-    def connect(self):
+    def connect(self):  # pylint: disable=no-self-use
         print("Please connect and turn on the device.")
 
     def disconnect(self):
@@ -148,20 +148,20 @@ class Device(serial.SerialDevice):
         if response != _DISCONNECTED_MESSAGE:
             raise exceptions.InvalidResponse(response=response)
 
-    def get_meter_info(self):
+    def get_meter_info(self):  # pylint: disable=no-self-use
         return common.MeterInfo('SD CodeFree glucometer')
 
-    def get_version(self):
+    def get_version(self):  # pylint: disable=no-self-use
         raise NotImplementedError
 
-    def get_serial_number(self):
+    def get_serial_number(self):  # pylint: disable=no-self-use
         raise NotImplementedError
 
-    def get_glucose_unit(self):
+    def get_glucose_unit(self):  # pylint: disable=no-self-use
         # Device does not provide information on glucose unit.
         return common.Unit.MG_DL
 
-    def get_datetime(self):
+    def get_datetime(self):  # pylint: disable=no-self-use
         raise NotImplementedError
 
     def set_datetime(self, date=datetime.datetime.now()):
@@ -189,10 +189,11 @@ class Device(serial.SerialDevice):
             self.send_message(_FETCH_MESSAGE)
             message = self.read_message()
 
-            r = _READING.parse(message)
-            logging.debug('received reading: %r', r)
+            reading = _READING.parse(message)
+            logging.debug('received reading: %r', reading)
 
             yield common.GlucoseReading(
                 datetime.datetime(
-                    2000 + r.year, r.month, r.day, r.hour, r.minute),
-                r.value, meal=r.meal)
+                    2000 + reading.year, reading.month,
+                    reading.day, reading.hour, reading.minute),
+                reading.value, meal=reading.meal)
diff --git a/glucometerutils/glucometer.py b/glucometerutils/glucometer.py
index 97fe80e..49569b0 100755
--- a/glucometerutils/glucometer.py
+++ b/glucometerutils/glucometer.py
@@ -19,58 +19,59 @@ from glucometerutils import exceptions
 def main():
     if sys.version_info < (3, 4):
         raise Exception(
-          'Unsupported Python version, please use at least Python 3.4')
+            'Unsupported Python version, please use at least Python 3.4')
 
     parser = argparse.ArgumentParser()
     subparsers = parser.add_subparsers(dest="action")
 
     parser.add_argument(
-      '--driver', action='store', required=True,
-      help='Select the driver to use for connecting to the glucometer.')
+        '--driver', action='store', required=True,
+        help='Select the driver to use for connecting to the glucometer.')
     parser.add_argument(
-      '--device', action='store', required=False,
-      help=('Select the path to the glucometer device. Some devices require this '
-            'argument, others will try autodetection.'))
+        '--device', action='store', required=False,
+        help=('Select the path to the glucometer device. Some devices require '
+              'this argument, others will try autodetection.'))
 
     parser.add_argument(
-      '--vlog', action='store', required=False, type=int,
-      help=('Python logging level. See the levels at '
-            'https://docs.python.org/3/library/logging.html#logging-levels'))
+        '--vlog', action='store', required=False, type=int,
+        help=('Python logging level. See the levels at '
+              'https://docs.python.org/3/library/logging.html#logging-levels'))
 
     subparsers.add_parser(
-      'help', help=('Display a description of the driver, including supported '
-                    'features and known quirks.'))
+        'help', help=('Display a description of the driver, including '
+                      'supported features and known quirks.'))
     subparsers.add_parser(
-      'info', help='Display information about the meter.')
+        'info', help='Display information about the meter.')
     subparsers.add_parser(
-      'zero', help='Zero out the data log of the meter.')
+        'zero', help='Zero out the data log of the meter.')
 
     parser_dump = subparsers.add_parser(
-      'dump', help='Dump the readings stored in the device.')
+        'dump', help='Dump the readings stored in the device.')
     parser_dump.add_argument(
-      '--unit', action='store',
-      choices=[unit.value for unit in common.Unit],
-      help='Select the unit to use for the dumped data.')
+        '--unit', action='store',
+        choices=[unit.value for unit in common.Unit],
+        help='Select the unit to use for the dumped data.')
     parser_dump.add_argument(
-      '--with-ketone', action='store_true', default=False,
-      help='Enable ketone reading if available on the glucometer.')
+        '--with-ketone', action='store_true', default=False,
+        help='Enable ketone reading if available on the glucometer.')
 
     parser_date = subparsers.add_parser(
-      'datetime', help='Reads or sets the date and time of the glucometer.')
+        'datetime', help='Reads or sets the date and time of the glucometer.')
     parser_date.add_argument(
-      '--set', action='store', nargs='?', const='now', default=None,
-      help='Set the date rather than just reading it from the device.')
+        '--set', action='store', nargs='?', const='now', default=None,
+        help='Set the date rather than just reading it from the device.')
 
     args = parser.parse_args()
 
     logging.basicConfig(level=args.vlog)
 
     try:
-        driver = importlib.import_module('glucometerutils.drivers.' + args.driver)
+        driver = importlib.import_module(
+            'glucometerutils.drivers.' + args.driver)
     except ImportError as e:
         logging.error(
-          'Error importing driver "%s", please check your --driver parameter:\n%s',
-          args.driver, e)
+            'Error importing driver "%s", please check your --driver '
+            'parameter:\n%s', args.driver, e)
         return 1
 
     # This check needs to happen before we try to initialize the device, as the
@@ -91,7 +92,7 @@ def main():
             except NotImplementedError:
                 time_str = 'N/A'
             print("{device_info}Time: {time}".format(
-              device_info=str(device_info), time=time_str))
+                device_info=str(device_info), time=time_str))
         elif args.action == 'dump':
             unit = args.unit
             if unit is None:
@@ -114,7 +115,8 @@ def main():
                     new_date = date_parser.parse(args.set)
                 except ImportError:
                     logging.error(
-                      'Unable to import module "dateutil", please install it.')
+                        'Unable to import module "dateutil", '
+                        'please install it.')
                     return 1
                 except ValueError:
                     logging.error('%s: not a valid date', args.set)
@@ -137,3 +139,4 @@ def main():
         return 1
 
     device.disconnect()
+    return 0
diff --git a/glucometerutils/support/freestyle.py b/glucometerutils/support/freestyle.py
index 5822d18..2206821 100644
--- a/glucometerutils/support/freestyle.py
+++ b/glucometerutils/support/freestyle.py
@@ -18,7 +18,7 @@ import re
 
 try:
     from typing import Iterator, List, Text, Tuple
-except:
+except ImportError:
     pass
 
 import construct
@@ -110,8 +110,7 @@ class FreeStyleHidDevice(hiddevice.HidDevice):
         usb_packet = _FREESTYLE_MESSAGE.build(
             {'message_type': message_type, 'command': command})
 
-        logging.debug('Sending packet: %r', usb_packet
-)
+        logging.debug('Sending packet: %r', usb_packet)
         self._write(usb_packet)
 
     def _read_response(self):
diff --git a/glucometerutils/support/hiddevice.py b/glucometerutils/support/hiddevice.py
index 1c5b58d..12debf8 100644
--- a/glucometerutils/support/hiddevice.py
+++ b/glucometerutils/support/hiddevice.py
@@ -11,13 +11,13 @@ import os
 
 try:
     from typing import BinaryIO, Optional, Text
-except:
+except ImportError:
     pass
 
 from glucometerutils import exceptions
 
 
-class HidDevice(object):
+class HidDevice:
     """A device speaking USB HID protocol driver base.
 
     This class does not implement an actual driver by itself, but provides an
@@ -100,6 +100,6 @@ class HidDevice(object):
         """
         if self.handle_:
             return bytes(self.handle_.read(size))
-        else:
-            return bytes(self.hidapi_handle_.read(
-                size, timeout_ms=self.TIMEOUT_MS))
+
+        return bytes(self.hidapi_handle_.read(
+            size, timeout_ms=self.TIMEOUT_MS))
diff --git a/glucometerutils/support/lifescan.py b/glucometerutils/support/lifescan.py
index 13529ec..1b5cb2d 100644
--- a/glucometerutils/support/lifescan.py
+++ b/glucometerutils/support/lifescan.py
@@ -12,19 +12,21 @@ from glucometerutils import exceptions
 class MissingChecksum(exceptions.InvalidResponse):
     """The response misses the expected 4-digits checksum."""
     def __init__(self, response):
-        self.message = 'Response is missing checksum: %s' % response
+        super(MissingChecksum, self).__init__(
+            'Response is missing checksum: %s' % response)
 
 
 class InvalidSerialNumber(exceptions.Error):
     """The serial number is not as expected."""
     def __init__(self, serial_number):
-        self.message = 'Serial number %s is invalid.' % serial_number
+        super(InvalidSerialNumber, self).__init__(
+            'Serial number %s is invalid.' % serial_number)
 
 
 class MalformedCommand(exceptions.InvalidResponse):
     def __init__(self, message):
-        exceptions.InvalidResponse.__init__(
-          self, 'Malformed command: %s' % message)
+        super(MalformedCommand, self).__init__(
+            'Malformed command: %s' % message)
 
 
 def crc_ccitt(data):
@@ -49,4 +51,4 @@ def crc_ccitt(data):
         crc ^= (((crc << 8) & 0xffff) << 4) & 0xffff
         crc ^= (crc & 0xff) << 5
 
-    return (crc & 0xffff)
+    return crc & 0xffff
diff --git a/glucometerutils/support/lifescan_binary_protocol.py b/glucometerutils/support/lifescan_binary_protocol.py
index 8b37726..e08d39f 100644
--- a/glucometerutils/support/lifescan_binary_protocol.py
+++ b/glucometerutils/support/lifescan_binary_protocol.py
@@ -27,7 +27,7 @@ _LINK_CONTROL = construct.BitStruct(
     'sequence_number' / construct.Default(construct.Flag, False),
 )
 
-def LifeScanPacket(include_link_control):
+def LifeScanPacket(include_link_control):  # pylint: disable=invalid-name
     # type: (bool) -> construct.Struct
     if include_link_control:
         link_control_construct = _LINK_CONTROL
@@ -36,15 +36,15 @@ def LifeScanPacket(include_link_control):
 
     return construct.Struct(
         'data' / construct.RawCopy(
-                construct.Struct(
-                    construct.Const(b'\x02'),  # stx
-                    'length' / construct.Rebuild(
-                        construct.Byte, lambda this: len(this.message) + 6),
-                    'link_control' / link_control_construct,
-                    'message' / construct.Bytes(
-                        lambda this: this.length - 6),
-                    construct.Const(b'\x03'),  # etx
-                ),
+            construct.Struct(
+                construct.Const(b'\x02'),  # stx
+                'length' / construct.Rebuild(
+                    construct.Byte, lambda this: len(this.message) + 6),
+                'link_control' / link_control_construct,
+                'message' / construct.Bytes(
+                    lambda this: this.length - 6),
+                construct.Const(b'\x03'),  # etx
+            ),
         ),
         'checksum' / construct.Checksum(
             construct.Int16ul, lifescan.crc_ccitt, construct.this.data.data),
diff --git a/glucometerutils/support/serial.py b/glucometerutils/support/serial.py
index c46d819..8dfe297 100644
--- a/glucometerutils/support/serial.py
+++ b/glucometerutils/support/serial.py
@@ -11,7 +11,7 @@ import logging
 
 try:
     from typing import Optional, Text
-except:
+except ImportError:
     pass
 
 import serial
@@ -19,7 +19,7 @@ import serial
 from glucometerutils import exceptions
 
 
-class SerialDevice(object):
+class SerialDevice:
     """A Serial-connected glucometer driver base.
 
     This class does not implement an actual driver by itself, but provides an
-- 
cgit v1.2.3