def load_installed_version(self):
        installed_packages = get_installed_pypackages()
        if self.package in installed_packages:
            self.version = "=={}".format(
                installed_packages[self.package].version)
def EVT_MOTION(event):
  global _mpos
  if event.LeftIsDown():
    if _mpos:
      (x,y),(mx,my) = event.Position,_mpos
      rotangles[0] += y-my
      rotangles[1] += x-mx
      refresh()    
    _mpos = event.Position