def get_package_url(cls, package, session=None, silent=False):
        response = get("{}/packages/{}".format(cls.bower_base_uri, package))
        return response.json().get("url", None)
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