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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_interface_ip(self, interface_name):
 """Get the ip address for an interface. :param interface_name: interface_name as a string :return: ip address of interface as a string """

        ios_cfg = self._get_running_config()
        parse = HTParser(ios_cfg)
        children = parse.find_children("^interface %s" % interface_name)
        for line in children:
            if 'ip address' in line:
                ip_address = line.strip().split(' ')[2]
                LOG.debug("IP Address:%s", ip_address)
                return ip_address
        LOG.warning("Cannot find interface: %s", interface_name)
        return None