diff --git a/tests/artifacts/generate_stix.py b/tests/artifacts/generate_stix.py
index 1503529..418a732 100644
--- a/tests/artifacts/generate_stix.py
+++ b/tests/artifacts/generate_stix.py
@@ -23,22 +23,22 @@ def generate_test_stix_file(file_path):
     for d in domains:
         i = Indicator(indicator_types=["malicious-activity"], pattern="[domain-name:value='{}']".format(d), pattern_type="stix")
         res.append(i)
-        res.append(Relationship(i, 'indicates', malware))
+        res.append(Relationship(i, "indicates", malware))
 
     for p in processes:
         i = Indicator(indicator_types=["malicious-activity"], pattern="[process:name='{}']".format(p), pattern_type="stix")
         res.append(i)
-        res.append(Relationship(i, 'indicates', malware))
+        res.append(Relationship(i, "indicates", malware))
 
     for f in filenames:
         i = Indicator(indicator_types=["malicious-activity"], pattern="[file:name='{}']".format(f), pattern_type="stix")
         res.append(i)
-        res.append(Relationship(i, 'indicates', malware))
+        res.append(Relationship(i, "indicates", malware))
 
     for e in emails:
         i = Indicator(indicator_types=["malicious-activity"], pattern="[email-addr:value='{}']".format(e), pattern_type="stix")
         res.append(i)
-        res.append(Relationship(i, 'indicates', malware))
+        res.append(Relationship(i, "indicates", malware))
 
     bundle = Bundle(objects=res)
     with open(file_path, "w+") as f:
diff --git a/tests/conftest.py b/tests/conftest.py
index 9323d11..ee45c80 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -21,6 +21,6 @@ def indicator_file(request, tmp_path_factory):
 @pytest.fixture(scope="session", autouse=True)
 def clean_test_env(request, tmp_path_factory):
     try:
-        del os.environ['MVT_STIX2']
+        del os.environ["MVT_STIX2"]
     except KeyError:
         pass
diff --git a/tests/ios/test_backup_info.py b/tests/ios/test_backup_info.py
index ed41707..0509f6d 100644
--- a/tests/ios/test_backup_info.py
+++ b/tests/ios/test_backup_info.py
@@ -16,4 +16,4 @@ class TestBackupInfoModule:
         m = BackupInfo(base_folder=get_backup_folder(), log=logging)
         run_module(m)
         assert m.results["Build Version"] == "18C66"
-        assert m.results["IMEI"] == '42'
+        assert m.results["IMEI"] == "42"
diff --git a/tests/ios/test_datausage.py b/tests/ios/test_datausage.py
index feaa103..6053d65 100644
--- a/tests/ios/test_datausage.py
+++ b/tests/ios/test_datausage.py
@@ -24,7 +24,7 @@ class TestDatausageModule:
         m = Datausage(base_folder=get_backup_folder(), log=logging, results=[])
         ind = Indicators(log=logging)
         ind.parse_stix2(indicator_file)
-        # Adds a file that exists in the manifest
+        # Adds a file that exists in the manifest.
         ind.ioc_processes[0] = "CumulativeUsageTracker"
         m.indicators = ind
         run_module(m)
diff --git a/tests/utils.py b/tests/utils.py
index a9a2b0b..ebc0bfe 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -23,5 +23,6 @@ def get_artifact_folder():
 def get_backup_folder():
     return os.path.join(os.path.dirname(__file__), "artifacts", "ios_backup")
 
+
 def get_indicator_file():
-    print("PYTEST env", os.getenv('PYTEST_CURRENT_TEST'))
+    print("PYTEST env", os.getenv("PYTEST_CURRENT_TEST"))