def METHOD_NAME(self):
    """Custom variables for OpenBabel module."""
    txt = super(EB_OpenBabel, self).METHOD_NAME()
    if self.with_python:
        if LooseVersion(self.version) >= LooseVersion('2.4'):
            # since OpenBabel 2.4.0 the Python bindings under
            # ${PREFIX}/lib/python2.7/site-packages  rather than ${PREFIX}/lib
            ob_pythonpath = det_pylibdir()
        else:
            ob_pythonpath = 'lib'
        txt += self.module_generator.prepend_paths('PYTHONPATH', [ob_pythonpath])
    babel_libdir = os.path.join(self.installdir, 'lib', 'openbabel', self.version)
    txt += self.module_generator.set_environment('BABEL_LIBDIR', babel_libdir)
    babel_datadir = os.path.join(self.installdir, 'share', 'openbabel', self.version)
    txt += self.module_generator.set_environment('BABEL_DATADIR', babel_datadir)
    return txt