2 files changed, 7 insertions, 12 deletions

diff --git a/glucometerutils/support/contourusb.py b/glucometerutils/support/contourusb.py
index 6cd9442..876c534 100644
--- a/glucometerutils/support/contourusb.py
+++ b/glucometerutils/support/contourusb.py
@@ -11,16 +11,10 @@ http://protocols.ascensia.com/Programming-Guide.aspx
 
 """
 
-import csv
 import datetime
-import logging
 import re
-from typing import Dict, Iterator, List, Optional, Text, Tuple
+from typing import Dict, List, Optional, Text, Tuple
 
-import construct
-
-from glucometerutils import exceptions
-from glucometerutils.exceptions import InvalidResponse
 from glucometerutils.support import driver_base, hiddevice
 
 # regexr.com/4k6jb
@@ -88,7 +82,8 @@ class ContourHidDevice(driver_base.GlucometerDriver):
         while True:
             data = self._hid_session.read()
             dstr = data
-            result.append(dstr[4 : data[3] + 4])
+            data_end_idx = data[3] + 4
+            result.append(dstr[4:data_end_idx])
             if data[3] != self.blocksize - 4:
                 break
 
@@ -308,7 +303,7 @@ class ContourHidDevice(driver_base.GlucometerDriver):
                         result = self.checkframe(data[stx:])
                         tometer = "\x06"
                         self.state = self.mode_data
-                    except FrameError as e:
+                    except FrameError:
                         tometer = "\x15"  # Couldn't parse, <NAK>
                 else:
                     # Got something we don't understand, <NAK> it
diff --git a/glucometerutils/support/freestyle.py b/glucometerutils/support/freestyle.py
index b1eb2d2..c77282b 100644
--- a/glucometerutils/support/freestyle.py
+++ b/glucometerutils/support/freestyle.py
@@ -12,7 +12,6 @@ import csv
 import datetime
 import logging
 import re
-from abc import ABC
 from typing import AnyStr, Callable, Iterator, List, Optional, Text, Tuple
 
 import construct
@@ -185,7 +184,8 @@ class FreeStyleHidSession:
 
         if not encrypted or message_type in _ALWAYS_UNENCRYPTED_MESSAGES:
             message_length = usb_packet[1]
-            message_content = usb_packet[2 : 2 + message_length]
+            message_end_idx = 2 + message_length
+            message_content = usb_packet[2:message_end_idx]
         else:
             message_content = usb_packet[1:]
 
@@ -340,7 +340,7 @@ class FreeStyleHidDevice(driver_base.GlucometerDriver):
         except UnicodeDecodeError:
             raise ValueError("Only ASCII-safe names are tested working")
 
-        result = self._session.send_text_command(b"$ptname," + encoded_name)
+        self._session.send_text_command(b"$ptname," + encoded_name)
 
     def get_datetime(self):
         # type: () -> datetime.datetime