Added Another solution for question 13

[naveen675]

Using Filter function

[darkprinx]

Thanks for this! Two things before it's ready to merge: 1) the ```python fence you open is never closed, so the rest of the file after this point renders as code text instead of normal markdown; 2) the code itself looks incomplete — it defines check_number but never calls it, and ends up printing the letter count twice instead of printing letters and digits separately. Could you fix both?

[darkprinx]

Went ahead and merged this with a few fixes: closed the unclosed docstring/code fence, removed stray leading indentation that would've raised an IndentationError, and wired up check_number (it was defined but never called — the code called check_letter twice instead, so digits were never actually counted). It now prints both letters and digits as intended. Thanks for the contribution! 🎉