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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def initialize():

 """Initialize Qt, patching sys.exit and eventually setting up ETS"""

    # This doesn't create our QApplication, just holds a reference to
    # MAIN_APP, created above to show our splash screen as early as
    # possible
    app = qapplication()

    # --- Set application icon
    app.setWindowIcon(APP_ICON)

    #----Monkey patching QApplication
    class FakeQApplication(QApplication):
        """Spyder's fake QApplication"""
        def __init__(self, args):
            self = app  # analysis:ignore
        @staticmethod
        def exec_():
            """Do nothing because the Qt mainloop is already running"""
            pass
    from qtpy import QtWidgets
    QtWidgets.QApplication = FakeQApplication

    # ----Monkey patching sys.exit
    def fake_sys_exit(arg=[]):
        pass
    sys.exit = fake_sys_exit

    # ----Monkey patching sys.excepthook to avoid crashes in PyQt 5.5+
    if PYQT5:
        def spy_excepthook(type_, value, tback):
            sys.__excepthook__(type_, value, tback)
        sys.excepthook = spy_excepthook

    # Removing arguments from sys.argv as in standard Python interpreter
    sys.argv = ['']

    # Selecting Qt4 backend for Enthought Tool Suite (if installed)
    try:
        from enthought.etsconfig.api import ETSConfig
        ETSConfig.toolkit = 'qt4'
    except ImportError:
        pass

    return app