No module named QtOpenGL

Question

I have the following error while running a python package cvu(connectome visualization utility):

Traceback (most recent call last):
  File "/usr/local/bin/cvu", line 4, in <module>
    __import__('pkg_resources').run_script('cvu==0.5.2', 'cvu')
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 657, in run_script
    self.require(requires)[0].run_script(script_name, ns)
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 1437, in run_script
    exec(code, namespace, namespace)
  File "/usr/local/lib/python2.7/dist-packages/cvu-0.5.2-py2.7.egg/EGG-INFO/scripts/cvu", line 33, in <module>
    from cvu.main import main
  File "/usr/local/lib/python2.7/dist-packages/cvu-0.5.2-py2.7.egg/cvu/__init__.py", line 20, in <module>
    from .main import load_adj, load_parc, usage, main
  File "/usr/local/lib/python2.7/dist-packages/cvu-0.5.2-py2.7.egg/cvu/main.py", line 20, in <module>
    from gui import CvuGUI,ErrorHandler
  File "/usr/local/lib/python2.7/dist-packages/cvu-0.5.2-py2.7.egg/cvu/gui.py", line 24, in <module>
    from dataset import Dataset
  File "/usr/local/lib/python2.7/dist-packages/cvu-0.5.2-py2.7.egg/cvu/dataset.py", line 26, in <module>
    from dataview import (DataView,DVMayavi,DVMatrix,DVCircle)
  File "/usr/local/lib/python2.7/dist-packages/cvu-0.5.2-py2.7.egg/cvu/dataview.py", line 28, in <module>
    from chaco.api import (Plot,ArrayPlotData,ColorMapper,PlotGraphicsContext)
  File "/usr/lib/python2.7/dist-packages/chaco/api.py", line 37, in <module>
    from abstract_plot_renderer import AbstractPlotRenderer
  File "/usr/lib/python2.7/dist-packages/chaco/abstract_plot_renderer.py", line 7, in <module>
    from plot_component import PlotComponent
  File "/usr/lib/python2.7/dist-packages/chaco/plot_component.py", line 4, in <module>
    from enable.api import Component
  File "/usr/lib/python2.7/dist-packages/enable/api.py", line 21, in <module>
    from markers import MarkerTrait, marker_trait, MarkerNameDict, marker_names, \
  File "/usr/lib/python2.7/dist-packages/enable/markers.py", line 18, in <module>
    from compiled_path import CompiledPath
  File "/usr/lib/python2.7/dist-packages/enable/compiled_path.py", line 17, in <module>
    from toolkit import toolkit_object
  File "/usr/lib/python2.7/dist-packages/enable/toolkit.py", line 47, in <module>
    _init_toolkit()
  File "/usr/lib/python2.7/dist-packages/enable/toolkit.py", line 40, in _init_toolkit
    format_exception_only(t, v))
ImportError: Unable to import the image backend for the qt4 toolkit (reason: ['ImportError: No module named QtOpenGL\n']).

I have installed this

apt-get install python-qt4-gl

but stil I have the same error. I don't know what is wrong. Thanks for any guide.

edit

this is the script that run the pakcage:

run.py

#!/usr/bin/env python

import os
import sys 

#pyside can cause problems with old versions of enable
#however, forcing traits to use pyqt causes problems in anaconda
#We will let the user set this optionally, it is good for debugging to not set.

#os.environ['QT_API']='pyqt'
#os.environ['QT_API']='pyside'

#One or the other should usually be set so that matplotlib and pyface can
#communicate and use the right Qt backend
#pyside is a better default choice

scriptdir=os.getcwd()
python_cmd = 'pythonw' if sys.platform=='darwin' else 'python'
#arguments = '%s %s'%(scriptdir, " ".join(sys.argv[1:]))
#exec_cmd = "%s main.py %s" % (python_cmd, arguments)

arguments = '%s main.py %s %s' % (python_cmd, scriptdir, " ".join(sys.argv[1:]))

try:
    #see if cvu extracted locally 
    os.chdir(os.path.join(os.path.dirname(os.path.dirname(
        os.path.realpath(__file__))),'cvu'))
    os.system(arguments)

except OSError:
    #see if cvu installed to system python

    from cvu.main import main
    sys.argv = arguments.split()
    main()