How do I make a particle play once without turning off emit?

I'm trying to create tracer particles for a gun and this is what I have so far.

extends Particles

var Timer = 0

func _process(delta):
	
	Timer -= 0.01
	
	if Input.is_action_pressed("Fire") and Timer <= 0:
		emitting = true
		Timer = 1.0
	if Timer >= 0:
		emitting = false

I've experimented with using one shot but I have the same problem as when I'm using emit. When I use either of them it kills off the particle entirely and I want the particle to stay active so each tracer I fire off flies into the distance and then I can create another one on each mouse click. Does anyone know how I would achieve this in Godot? Is there a different function for particles that I'm missing?

To be specific what I'm looking for is the Particles.Play() equivalent in Unity.