How to use the pybase64._pybase64.b64decode function in pybase64

def standard_b64decode(s):
        """Decode bytes encoded with the standard Base64 alphabet.

        Argument ``s`` is a :term:`bytes-like object` or ASCII string to
        decode.

        The result is returned as a :class:`bytes` object.

        A :exc:`binascii.Error` is raised if the input is incorrectly padded.

        Characters that are not in the standard alphabet are discarded prior
        to the padding check.
        """
        return b64decode(s)

def urlsafe_b64decode(s):
        """Decode bytes using the URL- and filesystem-safe Base64 alphabet.

        Argument ``s`` is a :term:`bytes-like object` or ASCII string to
        decode.

        The result is returned as a :class:`bytes` object.

        A :exc:`binascii.Error` is raised if the input is incorrectly padded.

        Characters that are not in the URL-safe base-64 alphabet, and are not
        a plus '+' or slash '/', are discarded prior to the padding check.

        The alphabet uses '-' instead of '+' and '_' instead of '/'.
        """
        return b64decode(s, b'-_')