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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 _make_hook_dict(fun):
 """Ensure the given function has a xworkflows_hook attribute. That attribute has the following structure: """

    if not hasattr(fun, 'xworkflows_hook'):
        fun.xworkflows_hook = {
            HOOK_BEFORE: [],
            HOOK_AFTER: [],
            HOOK_CHECK: [],
            HOOK_ON_ENTER: [],
            HOOK_ON_LEAVE: [],
        }
    return fun.xworkflows_hook