The problems in the python visualization, using ivtk observation of pipeline failure-CodePudding

 the from TVTK. API import TVTK 
The from TVTK. Tools import ivtk 
The from pyface. API import GUI 

# visualization pipeline section 
S=TVTK. CubeSource (x_length=1.0, y_length=2.0, z_length=3.0) 
(m=TVTK PolyDataMapper input_connection=s.o utput_port) 
# graphics pipeline section 
A=TVTK. Actor (mapper=m) # to create an entity 

# to create a Crust with the window (Python Shell) 
GUI GUI ()=
Win=ivtk. IVTKWithCrustAndBrowser () 
Win. The open () 
Win. Scene. Add_actor (a) 

# error corrections 
Dialog=win. Control. CentralWidget (). The widget (0). The widget (0) 
The from pyface. Qt import QtCore 
Dialog. SetWindowFlags (QtCore. Qt. WindowFlags (0 x00000000)) 
Dialog. The show () 

# open interface message loop 
GUI. Start_event_loop ()

Learning python visualization in the mooc preliminary debugging through, when using ivtk observation line can't run,
The following mistakes always import a name 'PythonShell'

 ImportError: always import the name 'PythonShell

Is there a big can help me answer the question? Thank you very much!