diff --git a/tests/email/test_email.py b/tests/email/test_email.py
index 932e051..57b9ea5 100644
--- a/tests/email/test_email.py
+++ b/tests/email/test_email.py
@@ -36,7 +36,7 @@ def test_ses_client_initialisation_invalid_sender_email():
     with pytest.raises(ValueError) as e:
         SesClient("invalid_email", "us-west-2")
 
-    assert "Invalid sender email: The email address is not valid." in str(e.value)
+    assert "Invalid sender email: An email address must have an @-sign." in str(e.value)
 
 
 @mock_aws
@@ -60,7 +60,7 @@ def test_ses_client_send_invalid_recipient(mock_ses_client):
     with pytest.raises(ValueError) as e:
         mock_ses_client.send("invalid_email", "subject", "body")
 
-    assert "Invalid recipient email: The email address is not valid." in str(e.value)
+    assert "Invalid recipient email: An email address must have an @-sign." in str(e.value)
 
 
 @mock_aws
diff --git a/tests/http/dataset/test_dataset_api.py b/tests/http/dataset/test_dataset_api.py
index 322cbc7..59bba22 100644
--- a/tests/http/dataset/test_dataset_api.py
+++ b/tests/http/dataset/test_dataset_api.py
@@ -54,6 +54,7 @@ def test_post_json_success(mock_request):
         verify=True,
     )
 
+
 @patch("requests.request")
 def test_post_json_failure(mock_request):
     """
@@ -71,6 +72,7 @@ def test_post_json_failure(mock_request):
     with pytest.raises(Exception):
         mock_client.post_json()
 
+
 @patch("requests.request")
 def test_post_new_job_success(mock_request):
     """
@@ -105,6 +107,7 @@ def test_post_new_job_failure(mock_request):
     with pytest.raises(Exception):
         mock_client.post_new_job()
 
+
 @patch("builtins.open", new_callable=mock_open, read_data='{"key": "value"}')
 @patch("requests.request")
 def test_upload_json(mock_request, mock_open_file):