The review comment left by Jenkins should include a hyperlink to the log for the failed job, which contains verbose output from the pep8 or flake8 tool describing what specific lines of code aren't compliant with OpenStack's style requirements (we perform more static analysis in those jobs than simple PEP-8 validation) and which particular rules triggered the failure. From that information it should be possible to identify and correct the issues with your change.

You can also repeat these same checks yourself by running 'tox -e pep8' from your working copy of the repository, though you will probably need a fairly recent version of tox installed on your machine (I prefer to pip install the latest tox package from PyPI into a separate virtualenv and run that since globally installing packages with pip is a bit dangerous, but that's a topic for another question).

Please read PEP8 - Style guide for python: http://www.python.org/dev/peps/pep-0008/

It has the rules you need to follow

I would recommend flake8 to check this. The script, run_tests.sh also uses flake8 to check indentation errors. You can do ./run_tests -p, just to check for pep8 and indentation capability.