fp = ProgressCallingFile(fp, progress)
TypeError: __init__() takes exactly 4 arguments (3 given)
Correct, it should be fixed. The signature is actually ProgressCallingFile(fp, size, progress). Where did you get this? The documentation?
ProgressCallingFile(fp, size, progress)
Haven't tried it since I filed the issue, but I got the usage from here: https://github.com/lericson/simples3/blob/master/simples3/streaming.py#L64
Add test coverage to streaming
Prevents future issues like #16
Fix issue with progress on streaming uploads