What are meant by third party libraries in python

Answer 1

Libraries which does not come by default with python are third party libraries.

Answer 2

Thanks

Answer 3

Anyone can write a library and publish it for everyone to use. Most of these third party libraries are open source, so you can even go to their creator and request or propose changes, and bugfixes. The source code of these projects is usually hosted on a public version control server, such as github.
You can upload your own library to Pypi (Python Package Index) so that it can be installed via pip and used by any Python developer.
https://pypi.org/