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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 enable_chunked_encoding(self, chunk_size: Optional[int]=None) -> None: """Enables automatic chunked transfer encoding."""

        self._chunked = True

        if hdrs.CONTENT_LENGTH in self._headers:
            raise RuntimeError("You can't enable chunked encoding when "
                               "a content length is set")
        if chunk_size is not None:
            warnings.warn('Chunk size is deprecated #1615', DeprecationWarning)