docs: def ip_cmd(self, name):
          """
          Print ip of given container
          """
          if not self.container_exists(name=name):
              exit('Unknown container {0}'.format(name))
  
          ip = self.get_container_ip(name)
          if not ip:
              exit("Failed to get network address for"
                   " container {0}".format(name))
          else:
              echo(ip)