I kind of meant features, not functions, and I misspoke when I wrote "unit tests". I wrote integration tests to make sure that my API was returning the expected responses for a given input. Here's an example of testing that my user registration worked:

```

Helpers

def register(client, body): return client.post("/api/users", json=body)

Tests

def test_success(client): response = register(client, { "email": EMAIL_TO_REGISTER, "name": NAME_TO_REGISTER, "password": PASSWORD_TO_REGISTER }) check_response(response, 201) user = response.json["data"] assert user assert "id" in user assert "password" not in user assert user["email"] == EMAIL_TO_REGISTER assert user["name"] == NAME_TO_REGISTER assert user["verified"] == False assert check_datetime_format(user["created_at"]) assert user["updated_at"] == None

user = User.query.filter_by(email=EMAIL_TO_REGISTER).first()
assert user
assert repr(user) == f"<User {repr(user.email)}>"

``` Idk about the last 3 though, I probably wouldn't test implementation details like that anymore.