Convert CodeWriter tests to Py3 syntax.
Convert CodeWriter tests to Py3 syntax.

cython/cython,da-woods/cython,scoder/cython,cython/cython,scoder/cython,scoder/cython,cython/cython,da-woods/cython,da-woods/cython,scoder/cython,cython/cython,da-woods/cython