the initial error. py.test notices when this happens and prints a warning
Note that it is good practice to avoid asserts with side effects, something
-which is easy to do with py.test. XYZZY insert reference to where this is
-Or you can turn off assert reinterpretation by invoking py.test as
+which is easy to do with py.test.
+Or you can turn off assert re-interpretation by invoking py.test as