code: def test_isQObjectAlive():
      o1 = pg.QtCore.QObject()
      o2 = pg.QtCore.QObject()
      o2.setParent(o1)
      del o1
      assert not pg.Qt.isQObjectAlive(o2)
  
imports: import os
  import pytest
  import pyqtgraph
label_desc: Use image node_id 1 for calling a global function with example usage: test_isQObjectAlive() without return types