Find the 0 index value according to the 1 index

According to the result of List.Transpose.
I want to find if L2 level index [0] value 84 is true, that returns L2 level index [1] value.
Please tell me how to control the index.

liste = IN

z = []

for el in liste:
	for element in el:
		if element[0] == 84:

OUT= z

Or with nodes:


List.Transpose is actually complicating things. It’s easier to manage your lists separately.