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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 data_and_files(self, data=True, files=True, stream=None):
 """Retrieve body data. Returns a two-elements tuple of a :class:`~.MultiValueDict` containing data from the request body, and data from uploaded files. If the body data is not ready, return a :class:`~asyncio.Future` which results in the tuple. The result is cached. """

        if self.method in ENCODE_URL_METHODS:
            value = {}, None
        else:
            value = self.cache.get('data_and_files')

        if not value:
            return self._data_and_files(data, files, stream)
        elif data and files:
            return value
        elif data:
            return value[0]
        elif files:
            return value[1]
        else:
            return None