After upgrading PyVimeo from 0.4.1 to 1.0.8 (Python 2.7.6), every v.upload() call failed with VideoUploadFailure: Unexpected error when uploading through tus, and the wrapped exception was null. Rolling back to 0.4.1 worked around it. The 1.0.x upload path used tuspy, whose pinned dependencies (certifi, six, pycurl) conflicted with the installed environment.