def implemented_by(interface, cls):
    """
        Check if class claims to provide the interface.

        Note that classes that implement the :py:class:`.DynamicInterface`
        interface cannot dynamically claim to `implement` an interface,
        although individual instances can claim to `provide` an interface.

        :return bool: :py:obj:`True` if interface is implemented by the class,
            else :py:obj:`False`.
        """
    return issubclass(cls, interface._verified) or issubclass(cls,
        interface._unverified)
