Maya - PySide2 - Menu Section.py

# third party libraries
import pymel.core as pm

menus = [i for i in sorted(pm.lsUI(menus=True)) if isinstance(i.getParent(), pm.ui.Window) and isinstance(i, pm.ui.Menu)]

for i in sorted(menus):
    if i.shortName() == "Test":
        i.delete()
        break
        
test = pm.menu("Test", parent=pm.MelGlobals()["gMainWindow"]).asQtObject()

test.addSection("Bar")
test.addMenu("FOOBAR")