def interface(host):
 if (host == '0.0.0.0'):
  return '127.0.0.1'
 if (host == '::'):
  return '::1'
 return host

def interface ( host ) : if ( host == '0.0.0.0' ) : return '127.0.0.1' if ( host == '::' ) : return '::1' return host
return an ip address for a client connection given the server host .