使用pyqt4选择变形的对象

Question

  File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/matplotlib/backends/backend_qt5agg.py", line 193, in __draw_idle_agg
    if self.height() < 0 or self.width() < 0:
RuntimeError: wrapped C/C++ object of %S has been deleted

为什么它使用QT5文件？

我只导入了QT4。它在此之前一直工作正常并且代码确实继续运行，但在ide中打印出来。

from matplotlib.backends.backend_qt4agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.backends.backend_qt4agg import NavigationToolbar2QT as NavigationToolbar

阅读了类似的在线问题，我得到了你无法解决这个问题的要点吗？