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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_lldp_tlv(self, port_name, is_ncb=True, is_nb=False):
 """Function to Query LLDP TLV on the interface. """

        reply = None
        if is_ncb:
            reply = self.run_lldptool(["get-tlv", "-n", "-i", port_name,
                                       "-g", "ncb"])
        elif is_nb:
            reply = self.run_lldptool(["get-tlv", "-n", "-i", port_name,
                                       "-g", "nb"])
        else:
            LOG.error("Both NCB and NB are not selected to "
                      "query LLDP")
        return reply