Rama z-score failed  failed.

/net/marbles/raid1/dorothee/rerefine/cryoem/data_no_H/6qyz_4680/05_2022/6qyz_4680.pdb /net/marbles/raid1/dorothee/rerefine/cryoem/data_no_H/6qyz_4680/05_2022/6qyz_4680.map 4.6
Traceback (most recent call last):
  File "/net/marbles/raid1/dorothee/rerefine/cryoem/rerefine_script.py", line 379, in get_statistics
    self.json_data[p+'z_score'] = z_scores['W'][0]
TypeError: 'NoneType' object has no attribute '__getitem__'