diff --git a/folder.py b/folder.py
index 6cb88a9dd..519069e18 100644
--- a/folder.py
+++ b/folder.py
@@ -205,7 +205,7 @@ def precheck_folder_secure(ctx, coll):
     found, last_run = get_last_run_time(ctx, coll)
     if (not correct_copytovault_start_status(ctx, coll)
             or not correct_copytovault_start_location(coll)
-            or not misc.last_run_time_acceptable(coll, found, last_run, config.vault_copy_backoff_time)):
+            or not misc.last_run_time_acceptable(found, last_run, config.vault_copy_backoff_time)):
         return False
 
     return True
diff --git a/groups_import.py b/groups_import.py
index 34d71d8b1..c1c876d68 100644
--- a/groups_import.py
+++ b/groups_import.py
@@ -142,7 +142,7 @@ def parse_csv_file(ctx):
     # Start processing the actual group data rows
     for line in lines:
         row_number += 1
-        rowdata, error = process_csv_line(line)
+        rowdata, error = process_csv_line(ctx, line)
 
         if error is None:
             extracted_data.append(rowdata)
diff --git a/integration_tests.py b/integration_tests.py
index abfa859c9..f345b5c58 100644
--- a/integration_tests.py
+++ b/integration_tests.py
@@ -350,16 +350,16 @@ def _test_folder_secure_func(ctx, func):
      "test": lambda ctx: _call_msvc_json_arrayops(ctx, '["a", "b", "c"]', "", "size", 0, 3),
      "check": lambda x: x == 3},
     {"name": "msvc.json_objops.add_notexist_empty",
-     "test": lambda ctx: _call_msvc_json_objops(ctx, '', msi.kvpair(ctx, "e", "f"), 'add',  0),
+     "test": lambda ctx: _call_msvc_json_objops(ctx, '', msi.kvpair(ctx, "e", "f"), 'add', 0),
      "check": lambda x: x == '{"e": "f"}'},
     {"name": "msvc.json_objops.add_notexist_nonempty",
-     "test": lambda ctx: _call_msvc_json_objops(ctx, '{"a": "b"}', msi.kvpair(ctx, "e", "f"), 'add',  0),
+     "test": lambda ctx: _call_msvc_json_objops(ctx, '{"a": "b"}', msi.kvpair(ctx, "e", "f"), 'add', 0),
      "check": lambda x: x == '{"a": "b", "e": "f"}'},
     {"name": "msvc.json_objops.add_exist_nonempty",
-     "test": lambda ctx: _call_msvc_json_objops(ctx, '{"a": "b"}', msi.kvpair(ctx, "e", "g"), 'add',  0),
+     "test": lambda ctx: _call_msvc_json_objops(ctx, '{"a": "b"}', msi.kvpair(ctx, "e", "g"), 'add', 0),
      "check": lambda x: x == '{"a": "b", "e": "g"}'},
     {"name": "msvc.json_objops.get_exist",
-     "test": lambda ctx: _call_msvc_json_objops(ctx, '{"a": "b", "c": "d"}', msi.kvpair(ctx, "c", ""), 'get',  1),
+     "test": lambda ctx: _call_msvc_json_objops(ctx, '{"a": "b", "c": "d"}', msi.kvpair(ctx, "c", ""), 'get', 1),
      "check": lambda x: str(x) == "(['c'], ['d'])"},
     {"name": "msvc.json_objops.get_notexist",
      "test": lambda ctx: _call_msvc_json_objops(ctx, '{"a": "b", "c": "d"}', msi.kvpair(ctx, "e", ""), 'get',  1),
diff --git a/meta.py b/meta.py
index 829f60dfa..887401958 100644
--- a/meta.py
+++ b/meta.py
@@ -164,7 +164,7 @@ def is_json_metadata_valid(callback,
     :param metadata:        Pre-parsed JSON object
     :param ignore_required: Ignore required fields
 
-    :returns: Boolean indicating if JSON metadata us valid
+    :returns: Boolean indicating if JSON metadata is valid
     """
     try:
         return len(get_json_metadata_errors(callback,
@@ -271,7 +271,7 @@ def collection_has_cloneable_metadata(callback, coll):
 
 @api.make()
 def api_meta_remove(ctx, coll):
-    """Remove a collection's metadata JSON, if it exist."""
+    """Remove a collection's metadata JSON, if it exists."""
     log.write(ctx, 'Remove metadata of coll {}'.format(coll))
 
     try:
diff --git a/schema_transformation.py b/schema_transformation.py
index 35bc35dd9..d7f7cc947 100644
--- a/schema_transformation.py
+++ b/schema_transformation.py
@@ -66,6 +66,7 @@ def api_transform_metadata(ctx, coll, keep_metadata_backup=True):
         execute_transformation(ctx, metadata_path, transform, keep_metadata_backup)
     else:
         return api.Error('no_metadata', 'No metadata file found')
+    return None
 
 
 def get(ctx, metadata_path, metadata=None):
@@ -197,7 +198,7 @@ def rule_batch_transform_vault_metadata(rule_args, callback, rei):
             vault_package = '/'.join(path_parts[:5])
             metadata_path = meta.get_latest_vault_metadata_path(callback, vault_package)
             log.write(callback, "[METADATA] Checking whether metadata needs to be transformed: " + metadata_path)
-            if metadata_path  != '':
+            if metadata_path != '':
                 transform = get(callback, metadata_path)
                 if transform is not None:
                     log.write(callback, "[METADATA] Executing transformation for: " + metadata_path)
@@ -376,9 +377,7 @@ def html(f):
                                 re.split('\n{2,}', f.__doc__)))
 
     # Remove docstring.
-    description = re.sub('((:param).*)|((:returns:).*)', ' ', description)
-
-    return description
+    return re.sub('((:param).*)|((:returns:).*)', ' ', description)
 
 
 @rule.make(inputs=[], outputs=[0])
@@ -394,8 +393,8 @@ def rule_batch_vault_metadata_schema_report(ctx):
                      the metadata matches the JSON schema). match_schema only has a meaning if a metadata schema
                      could be found.
     """
-    results = dict()
-    schema_cache = dict()
+    results = {}
+    schema_cache = {}
 
     # Find all vault collections
     iter = genquery.row_iterator(
diff --git a/tests/conftest.py b/tests/conftest.py
index 70a2520b6..a7c983b15 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -228,7 +228,7 @@ def api_request(user, request, data, timeout=10):
     # Retrieve user cookies.
     csrf, session = user_cookies[user]
 
-    # Disable unsecure connection warning.
+    # Disable insecure connection warning.
     urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
 
     # Replace zone name with zone name from environment configuration.
@@ -286,7 +286,7 @@ def post_form_data(user, request, files):
     # Retrieve user cookies.
     csrf, session = user_cookies[user]
 
-    # Disable unsecure connection warning.
+    # Disable insecure connection warning.
     urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
 
     # Make POST request.
diff --git a/tools/arb-update-resources.py b/tools/arb-update-resources.py
index 20874af8f..48c93ecf7 100644
--- a/tools/arb-update-resources.py
+++ b/tools/arb-update-resources.py
@@ -53,7 +53,7 @@ def parse_args():
 
 def parse_cs_values(input):
     """Parses a comma-separated list of key:value pairs as a dict."""
-    result = dict()
+    result = {}
     for kv_pair in input.split(","):
         if kv_pair == "":
             continue
@@ -96,7 +96,7 @@ def setup_session(irods_environment_config, ca_file="/etc/pki/tls/certs/chain.cr
                     'encryption_num_hash_rounds': 16,
                     'encryption_salt_size': 8,
                     'ssl_context': ssl_context}
-    settings = dict()
+    settings = {}
     settings.update(irods_environment_config)
     settings.update(ssl_settings)
     settings["password"] = password
@@ -160,8 +160,8 @@ def call_rule(session, rulename, params, number_outputs, rule_engine='irods_rule
         output=output_params,
         **re_config)
 
-    outArray = myrule.execute()
-    buf = outArray.MsParam_PI[0].inOutStruct.stdoutBuf.buf.decode(
+    out_array = myrule.execute()
+    buf = out_array.MsParam_PI[0].inOutStruct.stdoutBuf.buf.decode(
         'utf-8').splitlines()
 
     return buf[:number_outputs]
@@ -208,7 +208,7 @@ def main():
                 print("Updating misc resources ...")
             call_rule_update_misc(session)
     except NetworkException:
-        print("Could not connect to iRODS sever ...")
+        print("Could not connect to iRODS server ...")
 
 
 if __name__ == '__main__':
diff --git a/unit-tests/test_util_misc.py b/unit-tests/test_util_misc.py
index cddbe5fcd..aa03ef2c2 100644
--- a/unit-tests/test_util_misc.py
+++ b/unit-tests/test_util_misc.py
@@ -18,23 +18,23 @@ class UtilMiscTest(TestCase):
 
     def test_last_run_time_acceptable(self):
         """Test the last run time for copy to vault"""
-        # No last run time (job hasn't be tried before)
+        # No last run time (job hasn't been tried before)
         found = False
         last_run = 1
-        self.assertEqual(last_run_time_acceptable("b", found, last_run, 300), True)
+        self.assertEqual(last_run_time_acceptable(found, last_run, 300), True)
 
         # Last run time greater than the backoff, so can run
         now = int(time.time())
         found = True
         copy_backoff_time = 300
         last_run = now - copy_backoff_time - 1
-        self.assertEqual(last_run_time_acceptable("b", found, last_run, copy_backoff_time), True)
+        self.assertEqual(last_run_time_acceptable(found, last_run, copy_backoff_time), True)
 
         # Last run time more recent than the backoff, so should not run
         found = True
         copy_backoff_time = 300
         last_run = now
-        self.assertEqual(last_run_time_acceptable("b", found, int(time.time()), copy_backoff_time), False)
+        self.assertEqual(last_run_time_acceptable(found, int(time.time()), copy_backoff_time), False)
 
     def test_human_readable_size(self):
         output = human_readable_size(0)
diff --git a/util/misc.py b/util/misc.py
index 12df2a0af..a7d1c4471 100644
--- a/util/misc.py
+++ b/util/misc.py
@@ -9,7 +9,7 @@
 from collections import OrderedDict
 
 
-def last_run_time_acceptable(coll, found, last_run, config_backoff_time):
+def last_run_time_acceptable(found, last_run, config_backoff_time):
     """Return whether the last run time is acceptable to continue with task."""
     now = int(time.time())
 
@@ -48,5 +48,5 @@ def remove_empty_objects(d):
         # Clean lists by filtering out empty objects.
         return [remove_empty_objects(item) for item in d if remove_empty_objects(item) not in (None, '', {}, [])]
     else:
-        # Return the value abecause it is not a dict or list.
+        # Return the value because it is not a dict or list.
         return d