Reloads messages catalogue if requested after more than one second
        since last reload

def get_catalogue(self, locale):
        """
        Reloads messages catalogue if requested after more than one second
        since last reload
        """
        if locale is None:
            locale = self.locale

        if locale not in self.catalogues or datetime.now() - self.last_reload > timedelta(seconds=1):
            self._load_catalogue(locale)
            self.last_reload = datetime.now()

        return self.catalogues[locale]