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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 read_arg(src, c):
 """Read the argument from buffer. Advances buffer until right before the end of the argument. :param Buffer src: a buffer of tokens :param str c: argument token (starting token) :return: the parsed argument :rtype: Arg """

    content = [c]
    while src.hasNext():
        if src.peek() in ARG_END_TOKENS:
            content.append(next(src))
            break
        else:
            content.append(read_tex(src))
    return Arg.parse(content)