How Would You Go About Detecting a Double-Tapped Key?

I have made keybindings that play an animation when held down or tapped, but how would I go about detecting whether or not a key ('w' for instance) is pressed twice in quick succession? I have seen many games do this where double-tapping 's' will make you do a backflip or something, so I know this is possible. Here is some code that I use for my current key-bindings if it helps at all:

m.KeyDown:connect(function(key)
	local player = game.Players.LocalPlayer
	local curr_stam = tonumber(player.PlayerGui.Stats.Frame.StaminaQuantity.Text)
	if key == "0" and curr_stam > 0 and game.Players.LocalPlayer.Character.Humanoid.WalkSpeed >= 16 then --"Shift to run" 0 == shift
		game.Players.LocalPlayer.Character.Humanoid.WalkSpeed = 50
	end
end)

m.KeyUp:connect(function(key)
	if key == "0" and game.Players.LocalPlayer.Character.Humanoid.WalkSpeed >= 16 then
		game.Players.LocalPlayer.Character.Humanoid.WalkSpeed = 16
	end
end)