Problem about uploading results to evaluation server

[Retiina]

Dear author, thanks for your work! Today I upload the 'valid_submission_sample' to the evaluation server, however, it reports an error like below:

Traceback (most recent call last):
  File "/worker/worker.py", line 302, in run
    root_dir = tempfile.mkdtemp(dir=temp_dir)
  File "/usr/local/lib/python2.7/tempfile.py", line 339, in mkdtemp
    _os.mkdir(file, 0700)
OSError: [Errno 30] Read-only file system: '/tmp/codalab/tmpcP1K7y'

Could you have a look about this? Thanks in advance!