How to write bash script to open vi and edit document?

I'd like to write a Bash script that essentially automates the following process:

1. Open the filename.pdf file with vi:

   vi filename.pdf
   

2. In vi command mode, delete lines 4-7:

   :4,7d
   

3. In vi command mode, tap Shift+O (capital oh) to create a new line:

   O
   

4. In vi insert mode, type two lesser-thans and two greater-thans:

   <<>>
   

5. Switch vi to command mode:

   ESC
   

6. In vi command mode, save file and quit vi:

   :wq
   

7. Run:

   echo "Complete."