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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 ismonitor(self):
 """Returns True if the interface is in monitor mode. Only available with Npcap."""

        if self.cache_mode is not None:
            return self.cache_mode
        try:
            res = (self.mode() == "monitor")
            self.cache_mode = res
            return res
        except Scapy_Exception:
            return False