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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def do_macro_arg(parser, token):
 """ Function taking a parsed template tag to a MacroArgNode. """

    # macro_arg takes no arguments, so we don't
    # need to split the token/do validation.
    nodelist = parser.parse(('endmacro_arg',))
    parser.delete_first_token()
    # simply save the contents to a MacroArgNode.
    return MacroArgNode(nodelist)