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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 document(info=None, input=None, output=None):
 """ Add extra information about request handler and its params """

    def wrapper(func):
        if info is not None:
            setattr(func, "_swg_info", info)
        if input is not None:
            setattr(func, "_swg_input", input)
        if output is not None:
            setattr(func, "_swg_output", output)
        return func

    return wrapper