def show_tree(model=None):
if model is None:<EOL><INDENT>model = mx.cur_model()<EOL><DEDENT>view = get_modeltree(model)<EOL>app = QApplication.instance()<EOL>if not app:<EOL><INDENT>raise RuntimeError("<STR_LIT>")<EOL><DEDENT>view.show()<EOL>app.exec_()<EOL>
Display the model tree window.

    Args:
        model: :class:`Model <modelx.core.model.Model>` object.
            Defaults to the current model.

    Warnings:
        For this function to work with Spyder, *Graphics backend* option
        of Spyder must be set to *inline*.