Open the brute.py file and edit the seed23words variable with your 23 words.

Then, run python brute.py.

It will give you 180 possible valid BIP39 seeds.

If the size of your seed is not 24, change the number 24 from this line (from brute.py):

for arridx in range(0,24):

The mnemonic.py file is copied from Trezor.

To make seed with dice and coin: BIP39 diceware.

. . .

Oops, I tried to invent the wheel. There is already advanced tool for this task: https://github.com/gurnec/btcrecover