How to use the fabric-shim.ChaincodeStub.RESPONSE_CODE function in fabric-shim

if (fcn === 'SuccessShim') {
            return Shim.success();
        }

        await this.testAll(stub);

        if (fcn === 'nopayload') {
            return shim.success();
        }

        if (fcn === 'myReturnCode') {
            let rc: number;
            rc = ChaincodeStub.RESPONSE_CODE.OK;
            rc = shim.RESPONSE_CODE.OK;
            rc = ChaincodeStub.RESPONSE_CODE.ERRORTHRESHOLD;
            rc = shim.RESPONSE_CODE.ERRORTHRESHOLD;
            rc = ChaincodeStub.RESPONSE_CODE.ERROR;
            rc = shim.RESPONSE_CODE.ERROR;
            rc++;
        }

        return shim.success(Buffer.from('all good'));
    }

return Shim.error(Buffer.from(err.message));
        }

        if (fcn === 'SuccessShim') {
            return Shim.success();
        }

        await this.testAll(stub);

        if (fcn === 'nopayload') {
            return shim.success();
        }

        if (fcn === 'myReturnCode') {
            let rc: number;
            rc = ChaincodeStub.RESPONSE_CODE.OK;
            rc = shim.RESPONSE_CODE.OK;
            rc = ChaincodeStub.RESPONSE_CODE.ERRORTHRESHOLD;
            rc = shim.RESPONSE_CODE.ERRORTHRESHOLD;
            rc = ChaincodeStub.RESPONSE_CODE.ERROR;
            rc = shim.RESPONSE_CODE.ERROR;
            rc++;
        }

        return shim.success(Buffer.from('all good'));
    }

it('should work', async () => {
            const cc = new Chaincode();
            const stub = sinon.createStubInstance(ChaincodeStub);
            stub.getFunctionAndParameters.returns({ fcn: 'initFunc', params: [] });
            let res = await cc.Init(stub);
            res.status.should.equal(ChaincodeStub.RESPONSE_CODE.OK);
            stub.getFunctionAndParameters.returns({ fcn: 'invokeFunc', params: [] });
            res = await cc.Invoke(stub);
            res.status.should.equal(ChaincodeStub.RESPONSE_CODE.OK);
        });

it('should work', async () => {
            const cc = new Chaincode();
            const stub = sinon.createStubInstance(ChaincodeStub);
            stub.getFunctionAndParameters.returns({ fcn: 'initFunc', params: [] });
            const res = await cc.Init(stub);
            res.status.should.equal(ChaincodeStub.RESPONSE_CODE.OK);
        });