  The 2019 edition of Stack Overflow developer survey highlights that, for the
first time, Python outperformed Java in terms of popularity. The gap between
Python and Java further widened in the 2020 edition of the survey.
Unfortunately, despite the rapid increase in Python's popularity, there are not
many testing and debugging tools that are designed for Python. This is in stark
contrast with the abundance of testing and debugging tools for Java. Thus,
there is a need to push research on tools that can help Python developers. One
factor that contributed to the rapid growth of Java testing and debugging tools
is the availability of benchmarks. A popular benchmark is the Defects4J
benchmark; its initial version contained 357 real bugs from 5 real-world Java
programs. Each bug comes with a test suite that can expose the bug. Defects4J
has been used by hundreds of testing and debugging studies and has helped to
push the frontier of research in these directions. In this project, inspired by
Defects4J, we create another benchmark database and tool that contain 493 real
bugs from 17 real-world Python programs. We hope our benchmark can help
catalyze future work on testing and debugging tools that work on Python
programs.
