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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 error403(error):
 """ Custom 403 page. """

    tb = error.traceback

    if isinstance(tb, dict) and "name" in tb and "uuid" in tb:
        return SimpleTemplate(PRIVATE_ACCESS_MSG).render(
            name=error.traceback["name"],
            uuid=error.traceback["uuid"]
        )

    return "Access denied!"