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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 _parse_host(cls, host='localhost', port=0):
 """ Parse provided hostname and extract port number :param host: Server hostname :type host: string :param port: Server port :return: Tuple of (host, port) :rtype: tuple """

        if not port and (host.find(':') == host.rfind(':')):
            i = host.rfind(':')
            if i >= 0:
                host, port = host[:i], host[i + 1:]
                try:
                    port = int(port)
                except ValueError:
                    raise OSError('nonnumeric port')
        return host, port