[pre-commit.ci] auto fixes from pre-commit.com hooks

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classquiz/helpers/hashcash.py

@@ -39,7 +39,6 @@ every time it is passed the same arguments.  'mint()' incorporates a random
 salt in stamps (as per the hashcash v.1 protocol).
 """
 
-
 from string import ascii_letters
 from math import ceil, floor
 import hashlib

classquiz/tests/test_server.py

@@ -12,7 +12,6 @@ from classquiz.tests import test_user_email, test_user_password, example_quiztiv
 from classquiz.tests import test_client, example_quiz, ValueStorage  # noqa : F401
 from fastapi.testclient import TestClient
 
-
 # @pytest.fixture
 # async def startup_and_shutdown_server():
 #     """Start server as test fixture and tear down after test"""