docs: def cmd_help(*args):
      """
      Arguments: [<command>]
      List available commands
      """
      if len(args) == 0:
          print("Possible commands are:")
          print("")
          for cmd_name in sorted(COMMANDS.keys()):
              cmd_func = COMMANDS[cmd_name]
              print("{}:".format(cmd_name))
              print("=" * (len(cmd_name) + 1))
              print("    {}".format(cmd_func.__doc__.strip()))
              print("")
      else:
          cmd_name = args[0]
          cmd_func = COMMANDS[cmd_name]
          print("{}:".format(cmd_name))
          print("=" * (len(cmd_name) + 1))
          print("    {}".format(cmd_func.__doc__.strip()))