code: def cmd_link(self, args):
          '''handle link commands'''
          if len(args) < 1:
              self.show_link()
          elif args[0] == "list":
              self.cmd_link_list()
          elif args[0] == "add":
              if len(args) != 2:
                  print("Usage: link add LINK")
                  return
              self.cmd_link_add(args[1:])
          elif args[0] == "ports":
              self.cmd_link_ports()
          elif args[0] == "remove":
              if len(args) != 2:
                  print("Usage: link remove LINK")
                  return
              self.cmd_link_remove(args[1:])
          else:
              print("usage: link <list|add|remove>"f cmd_link(self, args):
          '''handle link commands'''
          if len(args) < 1:
              self.show_link()
          elif args[0] == "list":
              self.cmd_link_list()
          elif args[0] == "add":
              if len(args) != 2:
                  print("Usage: link add LINK")
                  return
              self.cmd_link_add(args[1:])
          elif args[0] == "ports":
              self.cmd_link_ports()
          elif args[0] == "remove":
              if len(args) != 2:
                  print("Usage: link remove LINK")
                  return
              self.cmd_link_remove(args[1:])
          else:
              print("usage: link <list|add|remove>")
docs: handle link commands