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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 add_prefix(self, prefix, flags, prf):
 """Add network prefix. Args: prefix (str):
 network prefix. flags (str):
 network prefix flags, please refer thread documentation for details prf (str):
 network prf, please refer thread documentation for details """

        self._req('prefix add %s %s %s' % (prefix, flags, prf))
        time.sleep(1)
        self._req('netdataregister')