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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 do_mntr(self, params):
 """ \x1b[1mNAME\x1b[0m mntr - Executes the mntr four-letter command \x1b[1mSYNOPSIS\x1b[0m mntr [hosts] [match] \x1b[1mOPTIONS\x1b[0m * hosts: the hosts to connect to (default: the current connected host) * match: only output lines that include the given string (default: '') \x1b[1mEXAMPLES\x1b[0m > mntr zk_version 3.5.0--1, built on 11/14/2014 10:45 GMT zk_min_latency 0 zk_max_latency 8 zk_avg_latency 0 """

        hosts = params.hosts if params.hosts != "" else None

        if hosts is not None and invalid_hosts(hosts):
            self.show_output("List of hosts has the wrong syntax.")
            return

        if self._zk is None:
            self._zk = XClient()

        try:
            content = get_matching(self._zk.mntr(hosts), params.match)
            self.show_output(content)
        except XClient.CmdFailed as ex:
            self.show_output(str(ex))