import ( "github.com/hyperledger/fabric/core/chaincode/shim" ) type MyChaincode struct {} func (cc *MyChaincode) Invoke(stub shim.ChaincodeStubInterface) pb.Response { // Get the function name and arguments function, args := stub.GetFunctionAndParameters() // Set a key/value pair in the state if function == "set" { err := stub.PutState(args[0], []byte(args[1])) if err != nil { return shim.Error(err.Error()) } return shim.Success(nil) } // Get the value for a given key from the state if function == "get" { valueBytes, err := stub.GetState(args[0]) if err != nil { return shim.Error(err.Error()) } return shim.Success(valueBytes) } // Invoke another chaincode if function == "invokeOtherChaincode" { result, err := stub.InvokeChaincode(args[0], [][]byte{[]byte(args[1])}) if err != nil { return shim.Error(err.Error()) } return shim.Success(result.Payload) } return shim.Error("Invalid function name") }In the example, the `MyChaincode` struct implements the `Invoke` function of the `shim.Chaincode` interface. The function uses the `GetFunctionAndParameters` function to get the name of the function being invoked and its arguments. It then uses the `PutState` function to set a key/value pair in the state, or the `GetState` function to get the value for a given key from the state. Finally, it uses the `InvokeChaincode` function to invoke another chaincode. The `ChaincodeStub` interface belongs to the `github.com.hyperledger.fabric.core.chaincode.shim` package library.