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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 deprecate(message):
 """ Decorate a function to emit a deprecation warning with the given message. """

    @decorator
    def decorate(fn, *args, **kw):
        warnings.warn(message, DeprecationWarning, 2)
        return fn(*args, **kw)
    return decorate