matplotlib 作图时报错

Exception ignored in: <bound method PhotoImage.__del__ of <tkinter.PhotoImage object at 0x0000000014FCFB70>>
Traceback (most recent call last):
  File "C:\Python34\lib\tkinter\__init__.py", line 3383, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <bound method PhotoImage.__del__ of <tkinter.PhotoImage object at 0x0000000015251A58>>
Traceback (most recent call last):
  File "C:\Python34\lib\tkinter\__init__.py", line 3383, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop
Exception ignored in: <bound method PhotoImage.__del__ of <tkinter.PhotoImage object at 0x000000001556E940>>
Traceback (most recent call last):
  File "C:\Python34\lib\tkinter\__init__.py", line 3383, in __del__
    self.tk.call('image', 'delete', self.name)
RuntimeError: main thread is not in main loop

Tcl_AsyncDelete: async handler deleted by the wrong thread

用wxpy与好友自动回复图片，能正常运行回复3个图片，之后就开始报错，如上，不知道怎么回事，求解