Pyright flags the right hand side of the third line here as Object of type "overload" is not callable:
import PySide2.QtWidgets as widgets
app = widgets.QApplication(sys.argv)
The same applies to constructors and other methods of many more classes.
Note added after more research: Pyright seems to get confused by the try: import typing at the beginning of each of PySide's .pyi files.