Q$3$: Develop an Python application that prompts the user to enter three distinct letters from the English alphabet separately, irrespective of their case. The application first identifies and excludes the letter that appears last in alphabetical order. Using the remaining two letters entered by the user, the application should then return a list containing all possible $2-$letter combinations formatted in title case and organized in alphabetical order.

Here is an output sample. In this example, I entered $"D","e",$ and $"b"$ as my three letters. As a result, the program omitted $"e"$ and returned $"Bb","Bd","Db",$ and $"Dd"$ that were sorted in alphabetical order in a list.

Enter your letter #$1$: D

Enter your letter #$2$: e

Enter your letter #$3$: b

Here is your list:

$[\text{'}$Bb$\text{'},\text{'}$Bd$\text{'},\text{'}$Db$\text{'},\text{'}$Dd$\text{'}]($please follow the sample$)$