The sdist tarball on pypi does not contain all needed files. Eg the README.md is missing which leads to:

Traceback (most recent call last):
  File "setup.py", line 8, in <module>
    long_description=open("README.md", "r").read(),
FileNotFoundError: [Errno 2] No such file or directory: 'README.md'

Not sure how you created the sdist, but you can just do:

python setup.py sdist

And then upload the tarball from the dist dir. I tried that locally and the sdist tarball I created was complete.