How to get roblox avatar urls from a roblox id?

So if you look to the top right of your screen currently, you will see a little roblox avatar, so somehow when I signed up, scripting helpers was able to find the URL of my roblox avatar. So if you right-click on that avatar and get the image address twice, it brings you to the roblox cdn and for me, my link looks like this. https://tr.rbxcdn.com/e15c76604406ca94b806b62a5866cfd7/200/200/Avatar/Png

so the part I don't understand is how the e15c76604406ca94b806b62a5866cfd7 part was obtained from my roblox id which is just 112017276. I am assuming this was done by the roblox API but I cant seem to find which endpoint is used for this.