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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 dark(app):
 """ Apply Dark Theme to the Qt application instance. Args: app (QApplication):
 QApplication instance. """


    _apply_base_theme(app)

    darkPalette = QPalette()

    # base
    darkPalette.setColor(QPalette.WindowText, QColor(180, 180, 180))
    darkPalette.setColor(QPalette.Button, QColor(53, 53, 53))
    darkPalette.setColor(QPalette.Light, QColor(180, 180, 180))
    darkPalette.setColor(QPalette.Midlight, QColor(90, 90, 90))
    darkPalette.setColor(QPalette.Dark, QColor(35, 35, 35))
    darkPalette.setColor(QPalette.Text, QColor(180, 180, 180))
    darkPalette.setColor(QPalette.BrightText, QColor(180, 180, 180))
    darkPalette.setColor(QPalette.ButtonText, QColor(180, 180, 180))
    darkPalette.setColor(QPalette.Base, QColor(42, 42, 42))
    darkPalette.setColor(QPalette.Window, QColor(53, 53, 53))
    darkPalette.setColor(QPalette.Shadow, QColor(20, 20, 20))
    darkPalette.setColor(QPalette.Highlight, QColor(42, 130, 218))
    darkPalette.setColor(QPalette.HighlightedText, QColor(180, 180, 180))
    darkPalette.setColor(QPalette.Link, QColor(56, 252, 196))
    darkPalette.setColor(QPalette.AlternateBase, QColor(66, 66, 66))
    darkPalette.setColor(QPalette.ToolTipBase, QColor(53, 53, 53))
    darkPalette.setColor(QPalette.ToolTipText, QColor(180, 180, 180))

    # disabled
    darkPalette.setColor(QPalette.Disabled, QPalette.WindowText,
                         QColor(127, 127, 127))
    darkPalette.setColor(QPalette.Disabled, QPalette.Text,
                         QColor(127, 127, 127))
    darkPalette.setColor(QPalette.Disabled, QPalette.ButtonText,
                         QColor(127, 127, 127))
    darkPalette.setColor(QPalette.Disabled, QPalette.Highlight,
                         QColor(80, 80, 80))
    darkPalette.setColor(QPalette.Disabled, QPalette.HighlightedText,
                         QColor(127, 127, 127))

    app.setPalette(darkPalette)