def get_ui_library():
    """
    Returns the library that is being used
    """
    try:
        import PyQt5
        qt = 'PyQt5'
    except ImportError:
        try:
            import PyQt4
            qt = 'PyQt4'
        except ImportError:
            try:
                import PySide2
                qt = 'PySide2'
            except ImportError:
                try:
                    import PySide
                    qt = 'PySide'
                except ImportError:
                    raise ImportError('No valid Gui library found!')
    return qt
