uses python-gettext to compile the binary of translation files instead of the shell "msgfmt" script

django compilemessages on os x

# after pip installing python-gettext
# these lines go in django.core.management.commands.compilemessages
# they replace the call to "os.system"

from pythongettext import msgfmt
po = msgfmt.Msgfmt(pf + '.po')
moo_file = pf + '.mo'
with open(moo_file, 'w') as f:
    f.write(po.get())