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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 mock_decorator(*a, **k):
 """ An pass-through decorator that returns the underlying function. This is used as the default for replacing decorators. """

    # This is a decorator without parameters, e.g.
    #
    # @login_required
    # def some_view(request):
    #     ...
    #
    if a:
        # This could fail in the instance where a callable argument is passed
        # as a parameter to the decorator!
        if callable(a[0]):
            def wrapper(*args, **kwargs):
                return a[0](*args, **kwargs)
            return wrapper

    # This is a decorator with parameters, e.g.
    #
    # @render_template("index.html")
    # def some_view(request):
    #     ...
    #
    def real_decorator(function):
        def wrapper(*args, **kwargs):
            return function(*args, **kwargs)
        return wrapper
    return real_decorator