code: func (stub *MockStub) MockPeerChaincode(invokableChaincodeName string, otherStub *MockStub) {
  	stub.Invokables[invokableChaincodeName] = otherStub
  }
docs: // Register a peer chaincode with this MockStub
  // invokableChaincodeName is the name or hash of the peer
  // otherStub is a MockStub of the peer, already intialised