Getting speedlimits along an itenerary or set of gps points

Hello everyone,

I am building an App using Python to compute a speed profile (using speedlimits) between two adresses or two coordinates. My final goal is to determine my car consumption for a giving itenerary. For that, my consumption model needs the travelling distance and the maximum speed my vehicle is reaching. Since I won't always have a GPS recording, I was thinking I could use the speedlimits as targets for my vehicle (of course if we respect the speedlimits ^^). I am sure it is feasible because it is almost what Google map would do to compute the traveling time.

Any idea how I could script that or maybe use some tools (free of course ^^)?

Thank you all.