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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 open(self, host, port=23):
 """Opens a telnet connection to the desired AttenuatorDevice and queries basic information. Args: host: A valid hostname (IP address or DNS-resolvable name) to an MC-DAT attenuator instrument. port: An optional port number (defaults to telnet default 23) """

        self._telnet_client.open(host, port)
        config_str = self._telnet_client.cmd("MN?")
        if config_str.startswith("MN="):
            config_str = config_str[len("MN="):]
        self.properties = dict(
            zip(['model', 'max_freq', 'max_atten'], config_str.split("-", 2)))
        self.max_atten = float(self.properties['max_atten'])