code: def arg_value(node, arg):
      """Retrieves a keyword argument's value from the node's keywords.
  
      Args:
          node (ast.Call): a node that represents a function call. For more,
              see https://docs.python.org/3/library/ast.html#abstract-grammar.
          arg (str): the name of the argument.
  
      Returns:
          obj: the keyword argument's value.
  
      Raises:
          KeyError: if the node's keywords do not contain the argument.
      """
      keyword = arg_from_keywords(node, arg)
      if keyword is None:
          raise KeyError(
              "arg '{}' not found in call: {}".format(
                  arg, pasta.dump(node)
              )
          )
  
      return (
          getattr(keyword.value, keyword.value._fields[0], None)
          if keyword.value
          else None
      )
  
label_desc: Use image node_id 2 for calling a global function with example usage: arg_value(node, arg) and returns: unknown