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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def check(cls, video):
 """Check if the `video` can be processed. The `video` is considered invalid if not an instance of :attr:`video_types` or if the :attr:`required_hash` is not present in :attr:`~subliminal.video.Video.hashes` attribute of the `video`. :param video: the video to check. :type video: :class:`~subliminal.video.Video` :return: `True` if the `video` is valid, `False` otherwise. :rtype: bool """

        if not isinstance(video, cls.video_types):
            return False
        if cls.required_hash is not None and cls.required_hash not in video.hashes:
            return False

        return True