flake8 fixes

a stricter flake8 bump. mostly things around f strings and format
strings, but a couple of bad placeholder names in loops

app/celery/tasks.py

@@ -339,7 +339,7 @@ def save_api_email_or_sms(self, encrypted_notification):
         try:
             self.retry(queue=QueueNames.RETRY)
         except self.MaxRetriesExceededError:
-            current_app.logger.error('Max retry failed' + f"Failed to persist notification {notification['id']}")
+            current_app.logger.error(f"Max retry failed Failed to persist notification {notification['id']}")
 
 
 @notify_celery.task(bind=True, name="save-letter", max_retries=5, default_retry_delay=300)
@@ -604,7 +604,7 @@ def send_inbound_sms_to_service(self, inbound_sms_id, service_id):
                 self.retry(queue=QueueNames.RETRY)
             except self.MaxRetriesExceededError:
                 current_app.logger.error(
-                    f"Retry: send_inbound_sms_to_service has retried the max number of" +
+                    "Retry: send_inbound_sms_to_service has retried the max number of" +
                     f"times for service: {service_id} and inbound_sms {inbound_sms_id}"
                 )
         else:

app/clients/email/aws_ses.py

@@ -60,8 +60,8 @@ class AwsSesClient(EmailClient):
 
         # events are generally undocumented, but some that might be of interest are:
         # before-call, after-call, after-call-error, request-created, response-received
-        self._client.meta.events.register(f'request-created.ses.SendEmail', self.ses_request_created_hook)
-        self._client.meta.events.register(f'response-received.ses.SendEmail', self.ses_response_received_hook)
+        self._client.meta.events.register('request-created.ses.SendEmail', self.ses_request_created_hook)
+        self._client.meta.events.register('response-received.ses.SendEmail', self.ses_response_received_hook)
 
     def ses_request_created_hook(self, **kwargs):
         # request created may be called multiple times if the request auto-retries. We want to count all these as the

app/notifications/validators.py

@@ -244,7 +244,7 @@ def validate_address(service, letter_data):
     if not address.has_valid_last_line:
         if address.allow_international_letters:
             raise ValidationError(
-                message=f'Last line of address must be a real UK postcode or another country'
+                message='Last line of address must be a real UK postcode or another country'
             )
         raise ValidationError(
             message='Must be a real UK postcode'

app/platform_stats/rest.py

@@ -84,21 +84,21 @@ def get_usage_for_all_services():
         }
         combined[s.service_id] = entry
 
-    for l in letter_costs:
-        if l.service_id in combined:
-            combined[l.service_id].update({'letter_cost': float(l.letter_cost)})
+    for letter_cost in letter_costs:
+        if letter_cost.service_id in combined:
+            combined[letter_cost.service_id].update({'letter_cost': float(letter_cost.letter_cost)})
         else:
             letter_entry = {
-                "organisation_id": str(l.organisation_id) if l.organisation_id else "",
-                "organisation_name": l.organisation_name or "",
-                "service_id": str(l.service_id),
-                "service_name": l.service_name,
+                "organisation_id": str(letter_cost.organisation_id) if letter_cost.organisation_id else "",
+                "organisation_name": letter_cost.organisation_name or "",
+                "service_id": str(letter_cost.service_id),
+                "service_name": letter_cost.service_name,
                 "sms_cost": 0,
                 "sms_fragments": 0,
-                "letter_cost": float(l.letter_cost),
+                "letter_cost": float(letter_cost.letter_cost),
                 "letter_breakdown": ""
             }
-            combined[l.service_id] = letter_entry
+            combined[letter_cost.service_id] = letter_entry
     for service_id, breakdown in lb_by_service:
         combined[service_id]['letter_breakdown'] += (breakdown + '\n')
 

tests/app/authentication/test_authentication.py

@@ -253,7 +253,7 @@ def test_should_allow_valid_token_when_service_has_multiple_keys(client, sample_
     save_model_api_key(api_key)
     token = __create_token(sample_api_key.service_id)
     response = client.get(
-        '/notifications'.format(str(sample_api_key.service_id)),
+        '/notifications',
         headers={'Authorization': 'Bearer {}'.format(token)})
     assert response.status_code == 200
 

tests/app/broadcast_message/test_rest.py

@@ -412,7 +412,7 @@ def test_update_broadcast_message_status_rejects_approval_from_creator(
     )
 
     assert mock_task.called is False
-    assert f'cannot approve their own broadcast' in response['message']
+    assert 'cannot approve their own broadcast' in response['message']
 
 
 def test_update_broadcast_message_status_rejects_approval_of_broadcast_with_no_areas(
@@ -523,7 +523,7 @@ def test_update_broadcast_message_status_rejects_approval_from_user_not_on_that_
     )
 
     assert mock_task.called is False
-    assert f'cannot approve broadcast' in response['message']
+    assert 'cannot approve broadcast' in response['message']
 
 
 @pytest.mark.parametrize('current_status, new_status', [

tests/app/notifications/test_validators.py

@@ -354,9 +354,11 @@ def test_check_is_message_too_long_passes_for_long_email(sample_service):
     with pytest.raises(BadRequestError) as e:
         check_is_message_too_long(template_with_content)
     assert e.value.status_code == 400
-    expected_message = f'Your message is too long. ' \
-        f'Emails cannot be longer than 1000000 bytes. ' \
-        f'Your message is 1000084 bytes.'
+    expected_message = (
+        'Your message is too long. ' +
+        'Emails cannot be longer than 1000000 bytes. ' +
+        'Your message is 1000084 bytes.'
+    )
     assert e.value.message == expected_message
     assert e.value.fields == []
 

tests/app/service/test_url_for.py

@@ -25,7 +25,7 @@ def test_url_for_get_service_by_id(notify_api):
 def test_url_for_create_service(notify_api):
     with notify_api.test_request_context():
         url = url_for('service.create_service')
-        assert str(url) == '/service'.format(service_id)
+        assert str(url) == '/service'
 
 
 def test_url_for_update_service(notify_api):