Sometimes (when you aren’t really doing true TDD), you make a change that breaks a lot of tests. When this happens, nose’s output can be long and gross, especially if your tests use print statements to help debugging.
In this case, you really want to just fix the errors one at a time. Its handy to use the —stop (or -x) option of nosetests, which makes the run stop at the first sign of trouble.
This makes it easier to read the output and helps morale, since you can tackle one failure at a time.