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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 body(self):
 """Return the Message Body. If auto_decode is enabled, the body will automatically be decoded using decode('utf-8') if possible. :rtype: bytes|str|unicode """

        if not self._auto_decode:
            return self._body
        if 'body' in self._decode_cache:
            return self._decode_cache['body']
        body = try_utf8_decode(self._body)
        self._decode_cache['body'] = body
        return body