int size errors when uploading large file (8GB) on 32-bit machine (raspberry pi)

Error:

[Exception] Python int too large to convert to C long
[Thread Failure] Python int too large to convert to C long

Command line:
s4cmd put -c 4 /mnt/xfer/largefile s3://bucketarray/largefile

Platform: Debian on armv7l (Raspbian)
Software:

s4cmd=2.1.0+ds-1

Hypothesis: Some code somewhere is attempting to convert a large python into into a C 'long' which can vary in size between platforms. Probably needs to be a long long or something.

Start by reproducing `s4cmd put -c 4 /mnt/xfer/largefile s3://bucketarray/largefile` on the reported Debian armv7l/Raspbian platform and trace the upload path that raises the C long conversion error. Done means an 8GB upload completes successfully on a 32-bit machine without the reported exception.

Written by the indexing model from the issue text.