Saving Overpass query results to GeoJSON file with Python?

I have just started to use Python and I would like to make a query to Overpass and store the results in a geospatial format (e.g. GeoJSON).

As far as I know, there is a library called overpy that should be what I am looking for. After reading its documentation I came up with the following code:

import overpy

API = overpy.Overpass()

# Fetch highways within Granollers' city.

result = API.query("""
    area[name="Granollers"][admin_level=8];
    // query part for: “highway=*”

    (way["highway"](area);
    relation["highway"](area);
    );
    // print results
    out body;
    """)

The thing is that I am not familiar at all with python and I don't know how to store result as a GeoJSON file (Honestly, I don't even know what kind of thing result is -I tried with type(result) and I get overpy.Result as an output, which doesn't mean much to my poor knowledge). I have been reading overpy documentation but I haven't been able to figure it out.