A simple Python script to help you find id of Facebook
Just like you open your browser -> go to the Facebook Page -> right click and view source code -> ctrl + F to find profile_id in the source code.
Only requests, use pip to install it.
sudo pip install requests
python Facebook_ID_Finder.py target_address
It will print out the id from the address which you given.
Foe example:
python Facebook_ID_Finder.py https://www.facebook.com/prof.yeh/
There may occur the error because of the owner of your target address didn't allow his id reveal in public.