On a 4x4 board, find words that can be formed by a sequence of adjacent (top, bottom, left,right,diagonal) letters. Words must be 3 or more letters. You may move to any of 8 adjacent letters, however, a word should not have multiple instances of the same cell.

Note: The above is an example board. Your solution should accept any board layout of letters. To check if a string is a valid word, you may implement a naive dictionary solution for simplicity.

Please use Python and add comments

R R A E L M M o F s T E o K N A . T 1