def _get_context_id(self):
        """If this async is in a context set the context id."""

        from furious.context import get_current_context

        context_id = self._options.get('context_id')

        if context_id:
            return context_id

        try:
            context = get_current_context()
        except errors.NotInContextError:
            context = None
            self.update_options(context_id=None)

        if context:
            context_id = context.id
            self.update_options(context_id=context_id)

        return context_id
If this async is in a context set the context id.