def adata():
    adata = ad.AnnData(np.zeros((100, 100)))
    adata.obsm["o"] = np.zeros((100, 50))
    adata.varm["o"] = np.zeros((100, 50))
    return adata
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