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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 decode(self, data: bytes) -> bytes: """Decodes data according the specified Content-Encoding or Content-Transfer-Encoding headers value. """

        if CONTENT_TRANSFER_ENCODING in self.headers:
            data = self._decode_content_transfer(data)
        if CONTENT_ENCODING in self.headers:
            return self._decode_content(data)
        return data