'x.__repr__() <==> repr(x)'

def __repr__(self):

    def _getval(key):
        try:
            return self[key]
        except MissingInterpolationOption:
            return dict.__getitem__(self, key)
    return ('{%s}' % ',    '.join([('%s:    %s' % (repr(key), repr(_getval(key)))) for key in (self.scalars + self.sections)]))
