    # File lib/fog/aws/requests/compute/attach_network_interface.rb, line 36
            def attach_network_interface(nic_id, instance_id, device_index)
              response = Excon::Response.new
              if self.data[:network_interfaces][nic_id]
                attachment = self.data[:network_interfaces][nic_id]['attachment']
                attachment['attachmentId'] = Fog::AWS::Mock.request_id
                attachment['instanceId']   = instance_id

                response.status = 200
                response.body = {
                  'requestId'    => Fog::AWS::Mock.request_id,
                  'attachmentId' => attachment['attachmentId']
                }
              else
                raise Fog::Compute::AWS::NotFound.new("The network interface '#{nic_id}' does not exist")
              end

              response
            end