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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 enable_global_auto_override_decorator(flag = True, retrospective = True):
 """Enables or disables global auto_override mode via decorators. See flag global_auto_override_decorator. In contrast to setting the flag directly, this function provides a retrospective option. If retrospective is true, this will also affect already imported modules, not only future imports. """

    global global_auto_override_decorator
    global_auto_override_decorator = flag
    if import_hook_enabled:
        _install_import_hook()
    if global_auto_override_decorator and retrospective:
        _catch_up_global_auto_override_decorator()
    return global_auto_override_decorator