tm.external_error_raised instead of tm.assertRaises in the documentation
I tried to use tm.assertRaises but got the following error:

 with tm.assertRaises(ValueError):
AttributeError: module 'pandas.util.testing' has no attribute 'assertRaises'

After carefully assessing whether I had all the dependencies, I looked into the testing.py files and realised that there is no assertRaises function although the testing documentation advises to use the function.(https://github.com/pandas-dev/pandas/wiki/Testing) I believe the documentation should be updated to tm.external_error_raised.