test-demandimport.py: PyPy support The stringification of sys.stderr is different in PyPy: $ pypy -c 'import sys; print sys.stderr' <open file '<fdopen>', mode 'w' at 0x00a42080> $ python -c 'import sys; print sys.stderr' <open file '<stderr>', mode 'w' at 0x10025a270> The test will now ignore the exact value between the angle brackets.