Define a function called letters that takes a string called text and returns a dictionary. The dictionary should have $26$ keys $--$ one for each letter of the alphabet $($count $\text{'}$a$\text{'}$ and $"$A$"$ both as occurrences of $\text{'}$a$\text{'})--$ and the value for each key should be the number of times that letter appears in the text.

$2.$ Write a program that calls letters on the following encrypted text file: encrypted.txt $($or use this version for mac$).$

Before our next class, use the link below to upload your letters function and the output of running letters on the encrypted file $($you can just upload the output as a separate file or include it as a comment in your main file $--$ if you're doing the optional bonus, do that before uploading so that you can upload a single file$).$