pip

Register a user and create config

[distutils]
index-servers = pypi

[pypi]
repository: https://pypi.python.org/pypi
username: user
password: xxx

Python2

Register a new package

python setup.py register -r pypi

Upload a new version of a package

python setup.py sdist upload -r pypi

Python3

First build the sdist

python setup.py sdist

Then install twine and upload it using this new tool

pip install twine
twine upload dist/*