Automation of setup.py and pip through Travis CI?

Is Travis CI necessary (or even helpful) for single developer github projects?

The way I presently work is I run setup.py sdist which generates the tar files for my package which I then upload to PyPi using twine.

I want to know how to use travis-ci for a simple project. Is there a simple hello world python project to do this? Its documentation seems complex and there seem to be multiple ways of configuring travis.yaml using tox, etc.

Mainly, I want to know:

1. Does travis automatically runs setup.py sdist for me?
2. How does it know when to trigger a build?
3. Where does it put the release tarballs?
4. Does it make a github release automatically too?

Also I'm thinking of adding unit testing to my packages. Is pytest the recommended or are there any other options too?