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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 port(self, value):
 """Set the connection's port property. Args: value: New port value. String. Returns: Nothing. """


        self._port = value
        # If port is None we remove the element and don't write it to XML
        if value is None:
            try:
                del self._connectionXML.attrib['port']
            except KeyError:
                pass
        else:
            self._connectionXML.set('port', value)