This tool encrypts files so that they can only be decrypted after an approximate amount of time. It uses the time lock puzzle written about here.
python3 timelock.py --num-squarings 1000000 encrypt example.png encrypted.enc
Set the --num-squarings parameter according to approximately how long you want the decryption to take. You can calculate this value by finding how many squarings per second your computer can calculate, and then multiplying by how many seconds you want the decryption to take. See benchmarking
python3 timelock.py decrypt encrypted.enc decrypted.png
Note that decryption in Python will take a long time compared to an optimized native program. In the future, the benchmarking program can be developed into a full decryption program.