AnimationPlayer changing for 'spamming' action inputs

Question

So my current code for animation player is "laggy" and doesn't change direction very quickly. How can I change the code so if players do spam the left and right buttons the animation player will respond accordingly? Here is the sprite sheet for reference: Sprite Sheet. My animation player is: .3 seconds with .1 steps and keyframes at 0, 1, 2, 0 for left animation and 3, 4, 5, 3 for right animation

func _fixed_process(delta):
    velocity.y += delta * GRAVITY
    if (Input.is_action_pressed("ui_left")):
        velocity.x = -WALK_SPEED
        if not animPlayer.is_playing():
            sprite.set_frame(0)
            animPlayer.play("walk_left")
    elif (Input.is_action_pressed("ui_right")):
        velocity.x = WALK_SPEED
        if not animPlayer.is_playing():
            sprite.set_frame(4)
            animPlayer.play("walk_right")

    else:
        velocity.x = 0

Comments

A side comment:
If that is your spritesheet, you can have a single "walk" animation and just flip texture when turning.

Answer 1

You have to check which animation is currently played. (getcurrentanimation ( ))

If your player is pressing right, while current animation is walk_left, you want to change that !

Also eventually stop the animation, and set it to its starting position when your player doesn't press any key. (or eventually start an "idle" animation)