--- a/toolkit/components/telemetry/.flake8
+++ b/toolkit/components/telemetry/.flake8
@@ -1,5 +1,5 @@
 [flake8]
 # See http://pep8.readthedocs.io/en/latest/intro.html#configuration
-ignore = E121, E123, E126, E129, E133, E226, E241, E242, E704, W503, E402, E502, E128, E501, E713, E222, E201, E202, W602, E127, W601
+ignore = E121, E123, E126, E129, E133, E226, E241, E242, E704, W503, E402, E128, E501, E713, E222, E201, E202, W602, E127, W601
 max-line-length = 99
 filename = *.py, +.lint

--- a/toolkit/components/telemetry/gen-histogram-data.py
+++ b/toolkit/components/telemetry/gen-histogram-data.py
@@ -15,17 +15,17 @@ import itertools
 banner = """/* This file is auto-generated, see gen-histogram-data.py.  */
 """
 
 
 def print_array_entry(output, histogram, name_index, exp_index, label_index, label_count):
     cpp_guard = histogram.cpp_guard()
     if cpp_guard:
         print("#if defined(%s)" % cpp_guard, file=output)
-    print("  { %s, %s, %s, %s, %d, %d, %s, %d, %d, %s }," \
+    print("  { %s, %s, %s, %s, %d, %d, %s, %d, %d, %s },"
         % (histogram.low(),
            histogram.high(),
            histogram.n_buckets(),
            histogram.nsITelemetry_kind(),
            name_index,
            exp_index,
            histogram.dataset(),
            label_index,

--- a/toolkit/components/telemetry/gen-scalar-data.py
+++ b/toolkit/components/telemetry/gen-scalar-data.py
@@ -36,17 +36,17 @@ def write_scalar_info(scalar, output, na
     :param output: the output stream.
     :param name_index: the index of the scalar name in the strings table.
     :param expiration_index: the index of the expiration version in the strings table.
     """
     cpp_guard = scalar.cpp_guard
     if cpp_guard:
         print("#if defined(%s)" % cpp_guard, file=output)
 
-    print("  {{ {}, {}, {}, {}, {}, {} }},"\
+    print("  {{ {}, {}, {}, {}, {}, {} }},"
           .format(scalar.nsITelemetry_kind,
                   name_index,
                   expiration_index,
                   scalar.dataset,
                   " | ".join(scalar.record_in_processes_enum),
                   "true" if scalar.keyed else "false"),
           file=output)
 

--- a/toolkit/components/telemetry/parse_events.py
+++ b/toolkit/components/telemetry/parse_events.py
@@ -129,20 +129,20 @@ def type_check_event_fields(identifier, 
     # Type-check fields.
     for k, v in definition.iteritems():
         ALL_FIELDS[k].check(identifier, k, v)
 
 
 def string_check(identifier, field, value, min_length=1, max_length=None, regex=None):
     # Length check.
     if len(value) < min_length:
-        raise ValueError("%s: value '%s' for field %s is less than minimum length of %d" %\
+        raise ValueError("%s: value '%s' for field %s is less than minimum length of %d" %
                          (identifier, value, field, min_length))
     if max_length and len(value) > max_length:
-        raise ValueError("%s: value '%s' for field %s is greater than maximum length of %d" %\
+        raise ValueError("%s: value '%s' for field %s is greater than maximum length of %d" %
                          (identifier, value, field, max_length))
     # Regex check.
     if regex and not re.match(regex, value):
         raise ValueError, '%s: string value "%s" for %s is not matching pattern "%s"' % \
                           (identifier, value, field, regex)
 
 
 class EventData:

--- a/toolkit/components/telemetry/parse_scalars.py
+++ b/toolkit/components/telemetry/parse_scalars.py
@@ -43,29 +43,29 @@ class ScalarType:
         :raises ValueError: if the length of the names exceeds the limit or they don't
                 conform our name specification.
         """
 
         # Enforce a maximum length on group and probe names.
         MAX_NAME_LENGTH = 40
         for n in [group_name, probe_name]:
             if len(n) > MAX_NAME_LENGTH:
-                raise ValueError("Name '{}' exceeds maximum name length of {} characters."\
+                raise ValueError("Name '{}' exceeds maximum name length of {} characters."
                                 .format(n, MAX_NAME_LENGTH))
 
         def check_name(name, error_msg_prefix, allowed_char_regexp):
             # Check if we only have the allowed characters.
             chars_regxp = r'^[a-zA-Z0-9' + allowed_char_regexp + r']+$'
             if not re.search(chars_regxp, name):
                 raise ValueError(error_msg_prefix + " name must be alpha-numeric. Got: '{}'".format(name))
 
             # Don't allow leading/trailing digits, '.' or '_'.
             if re.search(r'(^[\d\._])|([\d\._])$', name):
                 raise ValueError(error_msg_prefix +
-                    " name must not have a leading/trailing digit, a dot or underscore. Got: '{}'"\
+                    " name must not have a leading/trailing digit, a dot or underscore. Got: '{}'"
                     .format(name))
 
         check_name(group_name, 'Group', r'\.')
         check_name(probe_name, 'Probe', r'_')
 
     def validate_types(self, definition):
         """This function performs some basic sanity checks on the scalar definition:
             - Checks that all the required fields are available.
@@ -109,17 +109,17 @@ class ScalarType:
             raise KeyError(self._name + ' - missing required fields: ' + ', '.join(missing_fields))
 
         # Do we have any unknown field?
         unknown_fields = [f for f in definition.keys() if f not in ALL_FIELDS]
         if len(unknown_fields) > 0:
             raise KeyError(self._name + ' - unknown fields: ' + ', '.join(unknown_fields))
 
         # Checks the type for all the fields.
-        wrong_type_names = ['{} must be {}'.format(f, ALL_FIELDS[f].__name__) \
+        wrong_type_names = ['{} must be {}'.format(f, ALL_FIELDS[f].__name__)
             for f in definition.keys() if not isinstance(definition[f], ALL_FIELDS[f])]
         if len(wrong_type_names) > 0:
             raise TypeError(self._name + ' - ' + ', '.join(wrong_type_names))
 
         # Check that the lists are not empty and that data in the lists
         # have the correct types.
         list_fields = [f for f in definition if isinstance(definition[f], list)]
         for field in list_fields:
@@ -231,17 +231,17 @@ class ScalarType:
     def dataset(self):
         """Get the nsITelemetry constant equivalent to the chose release channel collection
         policy for the scalar.
         """
         # The collection policy is optional, but we still define a default
         # behaviour for it.
         release_channel_collection = \
             self._definition.get('release_channel_collection', 'opt-in')
-        return 'nsITelemetry::' +  ('DATASET_RELEASE_CHANNEL_OPTOUT' \
+        return 'nsITelemetry::' +  ('DATASET_RELEASE_CHANNEL_OPTOUT'
             if release_channel_collection == 'opt-out' else 'DATASET_RELEASE_CHANNEL_OPTIN')
 
     @property
     def cpp_guard(self):
         """Get the cpp guard for this scalar"""
         return self._definition.get('cpp_guard')