Python client for Isabelle server

We contribute a Python client for the Isabelle server, which gives researchers and students using Python as their primary programming language an opportunity to communicate with the Isabelle server through TCP directly from a Python script. Such an approach helps avoid the complexities of integrating the existing Python script with languages used for Isabelle development (ML and Scala). We also describe new features that appeared since the announcement of the first version of the client a year ago. Finally, we give examples of the client's applications in research and education and discuss known limitations and possible directions for future development.