Load a Qt Designer .ui file and returns an instance of the user interface

    Args:
        uifile (str): Absolute path to .ui file
        base_instance (QWidget): The widget into which UI widgets are loaded

    Returns:
        QWidget: the base instance

def setup_ui(uifile, base_instance=None):
    """Load a Qt Designer .ui file and returns an instance of the user interface

    Args:
        uifile (str): Absolute path to .ui file
        base_instance (QWidget): The widget into which UI widgets are loaded

    Returns:
        QWidget: the base instance

    """
    ui = QtCompat.loadUi(uifile)  # Qt.py mapped function
    if not base_instance:
        return ui
    else:
        for member in dir(ui):
            if not member.startswith('__') and \
               member is not 'staticMetaObject':
                setattr(base_instance, member, getattr(ui, member))
        return ui