async fn get_system_template_revisions(
        &self,
        input: GetSystemTemplateRevisionsRequest,
    ) -> Result<GetSystemTemplateRevisionsResponse, RusotoError<GetSystemTemplateRevisionsError>>
    {
        let mut request = self.new_signed_request("POST", "/");
        request.add_header(
            "x-amz-target",
            "IotThingsGraphFrontEndService.GetSystemTemplateRevisions",
        );
        let encoded = serde_json::to_string(&input).unwrap();
        request.set_payload(Some(encoded));

        let response = self
            .sign_and_dispatch(request, GetSystemTemplateRevisionsError::from_response)
            .await?;
        let mut response = response;
        let response = response.buffer().await.map_err(RusotoError::HttpDispatch)?;
        proto::json::ResponsePayload::new(&response)
            .deserialize::<GetSystemTemplateRevisionsResponse, _>()
    }
<p>Gets revisions made to the specified system template. Only the previous 100 revisions are stored. If the system has been deprecated, this action will return the revisions that occurred before its deprecation. This action won't work with systems that have been deleted.</p>
rusoto/services/iotthingsgraph/src/generated.rs