Log Message:
py-tqdm: updated to 4.31.1

v4.31.1:
fix file.encoding==None
add tests
tidy code, update authors and tests
add setup.py test to CI

v4.31.0:
Write bytes to stdout/stderr in py2
Add write_bytes parameter for py2/3 default override
support custom bar characters vias ascii parameter
implement, document and test custom bar spinners
support custom bar_format with unknown total
fix TypeError when unit_scale and unknown total
document format_dict
expose elapsed_s, remaining_s to bar_format
add unit option to bar_format
auto README.rst generation framework
add notes in CONTRIBUTING.md
update tests
update documentation
misc code tidy