code: private CreateVpcResponseType createVpc(final String cidrBlock, final String instanceTenancy) {
          CreateVpcResponseType ret = new CreateVpcResponseType();
          ret.setRequestId(UUID.randomUUID().toString());
  
          MockVpc mockVpc = mockVpcController.createVpc(cidrBlock, instanceTenancy);
          VpcType vpcType = new VpcType();
          vpcType.setVpcId(mockVpc.getVpcId());
          vpcType.setState(mockVpc.getState());
          vpcType.setCidrBlock(mockVpc.getCidrBlock());
          vpcType.setIsDefault(mockVpc.getIsDefault());
          ret.setVpc(vpcType);
  
          return ret;
      }
docs: Handles "createVpc" request and create new Vpc.
  @param cidrBlock : vpc cidrBlock.
  @param instanceTenancy : vpc instanceTenancy.
  @return a CreateVpcResponseType with new Vpc.