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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 get_vary_headers(self, request, response):
 """ Hook for patching the vary header """


        headers = []
        accessed = False
        try:
            accessed = request.session.accessed
        except AttributeError:
            pass

        if accessed:
            headers.append("Cookie")
        return headers