Count the elements in a List until an element is a TupleΒΆ

if isinstance(t, tuple)

Count the elements in a List until an element is a Tuple.
LOT = [
        10,
        20,
        30,
        (10,20),
        40
      ]
cnt = 0

for t in LOT:
    if isinstance(t, tuple):
        break
    cnt += 1
print(cnt)                     # 3