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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 check_pil(func):
 """ PIL module checking decorator. """

    def __wrapper(*args, **kwargs):
        root = kwargs.get('root')
        if not Image:
            if root and root.get_opt('warn'):
                warn("Images manipulation require PIL")
            return 'none'
        return func(*args, **kwargs)
    return __wrapper