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Tiny python docstring tip

Tomer
・1 min read

When defining interfaces in python using the abc.ABC metaclass, sometimes it gets pretty annoying to have so many empty methods, waiting to be filled in.

import abc
class Requester(abc.ABC):
    @abc.abstractmethod
    def get(self, endpoint:str) -> Response:
        """Sends a GET request."""
        pass

    @abc.abstractmethod
    def post(self, endpoint:str, params:dict) -> Response:
        """Makes a POST request."""
        pass
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All these uses of pass always felt pretty ugly to me, and luckily there is a solution!

Because docstrings are simply a string expression in the start of a function - you can just let go of the pass!

import abc
class Requester(abc.ABC):
    @abc.abstractmethod
    def get(self, url:str, url_params:dict) -> Response:
        """Sends a GET request."""

    @abc.abstractmethod
    def post(self, url:str, url_params:dict) -> Response:
        """Makes a POST request."""
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Now isn't that so much nicer?

Discussion (2)

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dperetti profile image
Dominique PERETTI

I would rather use stubs, as explained here github.com/python/mypy/wiki/Creati...

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tadaboody profile image
Tomer Author

Stubs and abstract classes aren't the same thing. Stubs annotate existing classes/interfaces/methods helping mypy make static checks.
while abstract classes declare new constructs, used to later be inherited from and implemented (with only runtime checks)