code: func (ec2i *FakeEC2Impl) CreateSubnet(request *ec2.Subnet) (*ec2.CreateSubnetOutput, error) {
  	ec2i.Subnets = append(ec2i.Subnets, request)
  	response := &ec2.CreateSubnetOutput{
  		Subnet: request,
  	}
  	return response, nil
  }
docs: // CreateSubnet creates fake subnets