This was something I created for my University Coursework in which I had to find the key for a viegenere cipher, where two words were encrypted with the same key within a list of words.
I wrote this script that would go through the list of words and find two words that had the same shift as the shift in the ciphertext as this would lead me to finding the key.
The shift relates to the letters position in the alphabet and can be adjusted in the file for your specific needs.
You can use any text file with one word per line as input. And this only works for ten letter words, as this is what I had to work with. But you can adjust it to work with more.