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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 call(self, name, request=None, **params):
 """ Call resource by ``Api`` name. :param name: The resource's name (short form) :param request: django.http.Request instance :param **params: Params for a resource's call :return object: Result of resource's execution """

        if name not in self.resources:
            raise exceptions.HttpError(
                'Unknown method \'%s\'' % name,
                status=status.HTTP_501_NOT_IMPLEMENTED)
        request = request or HttpRequest()
        resource = self.resources[name]
        view = resource.as_view(api=self)
        return view(request, **params)