The gettext module provides one additional class derived from NullTranslations: GNUTranslations. This class overrides _parse() to enable reading GNU gettext format .mo files in both big-endian and little-endian format.
It also parses optional meta-data out of the translation catalog. It
is convention with GNU gettext to include meta-data as the
translation for the empty string. This meta-data is in RFC 822 -style
key: value pairs. If the key
Content-Type is found,
charset property is used to initialize the
``protected'' _charset instance variable. The entire set of
key/value pairs are placed into a dictionary and set as the
``protected'' _info instance variable.
If the .mo file's magic number is invalid, or if other problems occur while reading the file, instantiating a GNUTranslations class can raise IOError.
The other usefully overridden method is ugettext(), which returns a Unicode string by passing both the translated message string and the value of the ``protected'' _charset variable to the builtin unicode() function.