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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 _zom_arg(lexer):
 """Return zero or more arguments."""

    tok = next(lexer)
    # ',' EXPR ZOM_X
    if isinstance(tok, COMMA):
        return (_expr(lexer), ) + _zom_arg(lexer)
    # null
    else:
        lexer.unpop_token(tok)
        return tuple()