I replaced my window regulator thing (the thing with prongs in a moon shape) because it got stuck at some parts i manage after a while to get the window and the regulator+motor with it out of the door (1997 HONDA CIVIC) i took off the motor and put it on the new one but when i was putting it back

I found a piece on the floor i have no clue where it came from. its black and its coiled like a spring with a small bend in the middle and the tail. do i need to put this piece back to something?

i need this done asap

 

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