pylint fails in the build environment

$ ./start-build-env.sh
(snip)
aajisaka@21a025f08d49:~/hadoop$ pylint
Traceback (most recent call last):
  File "/usr/local/bin/pylint", line 11, in <module>
    sys.exit(run_pylint())
  File "/usr/local/lib/python2.7/dist-packages/pylint/__init__.py", line 15, in run_pylint
    from pylint.lint import Run
  File "/usr/local/lib/python2.7/dist-packages/pylint/lint.py", line 67, in <module>
    from pylint import checkers
  File "/usr/local/lib/python2.7/dist-packages/pylint/checkers/__init__.py", line 45, in <module>
    from pylint.config import OptionsProviderMixIn
  File "/usr/local/lib/python2.7/dist-packages/pylint/config.py", line 49, in <module>
    import configparser
ImportError: No module named configparser