convert mysql query to django

Guys! I have this query that I want to use in Django and I can not find a way to do it. I hope you can help me:

SELECT herramienta_id, SUM(cantidad) FROM inventario_transaccion 
WHERE carrito_id=1 
GROUP BY herramienta_id

What I want to do is get a list of unique tools and do the sum of the amount. Example

herramienta   cantidad
+-----------+----------+
| martillo  |    2     |
| clavos    |    1     |
| martillo  |    1     |
+-----------+----------+

I get as a result

herramienta   cantidad
+-----------+----------+
| martillo  |    3     |
| clavos    |    1     |
+-----------+----------+