
Since pygments 2.5 `PythonLexer` refers to python3 [1]. We have to be explicit if we want to use python2. [1] https://pygments.org/docs/changelog/
Since pygments 2.5 `PythonLexer` refers to python3 [1]. We have to be explicit if we want to use python2. [1] https://pygments.org/docs/changelog/