code: def test_collect_traffic_light_bounds():
      test_dict = {"a": 2, "b:c": 5, "b:d": 6, "x:y:z": 17}
  
      pkeys, nkeys = collect_traffic_light_bounds(test_dict)
  
      assert nkeys == ["a"]
      assert len(pkeys) == 2
      assert pkeys["x:y"] == ["z"]
      assert set(pkeys["b"]) == {"c", "d"}
  
imports: import pytest
  from popmon.alerting import ComputeTLBounds, collect_traffic_light_bounds
label_desc: Use image node_id 1 for calling a global function with example usage: test_collect_traffic_light_bounds() without return types