async fn get_firewall_rule_group_association(
        &self,
        input: GetFirewallRuleGroupAssociationRequest,
    ) -> Result<
        GetFirewallRuleGroupAssociationResponse,
        RusotoError<GetFirewallRuleGroupAssociationError>,
    > {
        let mut request = self.new_signed_request("POST", "/");
        request.add_header(
            "x-amz-target",
            "Route53Resolver.GetFirewallRuleGroupAssociation",
        );
        let encoded = serde_json::to_string(&input).unwrap();
        request.set_payload(Some(encoded));

        let response = self
            .sign_and_dispatch(request, GetFirewallRuleGroupAssociationError::from_response)
            .await?;
        let mut response = response;
        let response = response.buffer().await.map_err(RusotoError::HttpDispatch)?;
        proto::json::ResponsePayload::new(&response)
            .deserialize::<GetFirewallRuleGroupAssociationResponse, _>()
    }
<p>Retrieves a firewall rule group association, which enables DNS filtering for a VPC with one rule group. A VPC can have more than one firewall rule group association, and a rule group can be associated with more than one VPC.</p>
rusoto/services/route53resolver/src/generated.rs