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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 _fetch(self, request):
 """ Fetch using the OkHttpClient """

        client = self.client

        #: Dispatch the async call
        call = Call(__id__=client.newCall(request.request))
        call.enqueue(request.handler)

        #: Save the call reference
        request.call = call