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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 retrieve(self, request):
 """Look up request in cache, skipping if verb is forbidden. :param requests.Request request: HTTP request """

        if request.method not in CACHE_VERBS:
            return
        try:
            response = self.data[request.url]['response']
            logger.info('Retrieved response from cache')
            return response
        except KeyError:
            return None