code: def parse_prefix(prefix, default_length=128):
      
      if '/' in prefix:
          network, pfxlen = prefix.split('/')
      else:
          network = prefix
          pfxlen = default_length
      return network, int(pfxlen)
docs: Splits the given IP prefix into a network address and a prefix length.
      If the prefix does not have a length (i.e., it is a simple IP address),
      it is presumed to have the given default length.
  
      :type  prefix: string
      :param prefix: An IP mask.
      :type  default_length: long
      :param default_length: The default ip prefix length.
      :rtype:  string, int
      :return: A tuple containing the IP address and prefix length.