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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 list_webhooks(self, scaling_group, policy):
 """ Returns a list of all webhooks for the specified policy. """

        uri = "/%s/%s/policies/%s/webhooks" % (self.uri_base,
                utils.get_id(scaling_group), utils.get_id(policy))
        resp, resp_body = self.api.method_get(uri)
        return [AutoScaleWebhook(self, data, policy, scaling_group)
                for data in resp_body.get("webhooks", [])]