Method contains

django/db/models/query.py:1441–1460

Return True if the QuerySet contains the provided obj, False otherwise.

(self, obj)

        return await sync_to_async(self.exists)()

    def contains(self, obj):
        """
        Return True if the QuerySet contains the provided obj,
        False otherwise.
        """
        self._not_support_combined_queries("contains")
        if self._fields is not None:
            raise TypeError(
                "Cannot call QuerySet.contains() after .values() or .values_list()."
            )
        try:
            if obj._meta.concrete_model != self.model._meta.concrete_model:
                return False
        except AttributeError:
            raise TypeError("'obj' must be a model instance.")
        if not obj._is_pk_set():
            raise ValueError("QuerySet.contains() cannot be used on unsaved objects.")
        if self._result_cache is not None:
            return obj in self._result_cache
        return self.filter(pk=obj.pk).exists()

    async def acontains(self, obj):
        return await sync_to_async(self.contains)(obj=obj)