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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 key_for_request(self, method, url, **kwargs):
 """ Return a cache key from a given set of request parameters. Default behavior is to return a complete URL for all GET requests, and None otherwise. Can be overriden if caching of non-get requests is desired. """

        if method != 'get':
            return None

        return requests.Request(url=url, params=kwargs.get('params', {})).prepare().url