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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 get_cdr(self, start=0, count=-1, **kwargs):
 """Request range of CDR messages"""

        sha = encode_to_sha("{:d},{:d}".format(start, count))
        return self._queue_msg({'cmd': cmd.CMD_MESSAGE_CDR,
                                'sha': sha}, **kwargs)