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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 _load_stream(self):
 """ Return the content body of the request, as a stream. """

        meta = self._request.META
        try:
            content_length = int(
                meta.get('CONTENT_LENGTH', meta.get('HTTP_CONTENT_LENGTH', 0))
            )
        except (ValueError, TypeError):
            content_length = 0

        if content_length == 0:
            self._stream = None
        elif hasattr(self._request, 'read'):
            self._stream = self._request
        else:
            self._stream = six.BytesIO(self.raw_post_data)