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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 decorator(d):
 """Creates a proper decorator. If the default for the first (function) argument is None, creates a See examples below. """

    defaults = d.__defaults__
    if defaults and defaults[0] is None:
        # Can be applied as @decorator or @decorator(kwargs) because
        # first argument is None
        def decorate(fn=None, **kwargs):
            if fn is None:
                return _functools.partial(decorate, **kwargs)
            else:
                decorated = d(fn, **kwargs)
                _functools.update_wrapper(decorated, fn)
                return decorated
    else:
        # Can only be applied as @decorator
        def decorate(fn):
            decorated = d(fn)
            _functools.update_wrapper(decorated, fn)
            return decorated
    _functools.update_wrapper(decorate, d)
    return decorate