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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 set_connection(self, service_name, to_cache):
 """ Sets a connection class within the cache. :param service_name: The service a given ``Connection`` talks to. Ex. ``sqs``, ``sns``, ``dynamodb``, etc. :type service_name: string :param to_cache: The class to be cached for the service. :type to_cache: class """

        self.services.setdefault(service_name, {})
        self.services[service_name]['connection'] = to_cache