Problems of plot.plot() on Ubuntu16.1

I have compiled the Yade on Ubuntu 16.1. However, there are some problems as follows when using plot.plot().
Anyone can help me?
Thanks !
Henry.

QObject::connect: Cannot connect NavigationToolbar2QT::message(QString) to (null)::_show_message()
Traceback (most recent call last):
  File "/usr/local/bin/yade", line 182, in runScript
    execfile(script,globals())
  File "uniax.py", line 173, in <module>
    plot.plot(subPlots=False)
  File "/usr/local/lib/x86_64-linux-gnu/yade-2017-01-04.git-8801250/py/yade/plot.py", line 592, in plot
    createPlots(subPlots=subPlots)
  File "/usr/local/lib/x86_64-linux-gnu/yade-2017-01-04.git-8801250/py/yade/plot.py", line 380, in createPlots
    if not subPlots: pylab.figure()
  File "/usr/lib/python2.7/dist-packages/matplotlib/pyplot.py", line 527, in figure
    **kwargs)
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_qt5agg.py", line 43, in new_figure_manager
    return new_figure_manager_given_figure(num, thisFig)
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_qt5agg.py", line 51, in new_figure_manager_given_figure
    return FigureManagerQT(canvas, num)
  File "/usr/lib/python2.7/dist-packages/matplotlib/backends/backend_qt5.py", line 465, in __init__
    self.toolbar.message.connect(self._show_message)
TypeError: connect() failed between NavigationToolbar2QT.message[str] and _show_message()