In the example below, we've sketched out main but have stubs returning dummy values for every function. The user can type anything at the prompt. The game loop continues until ENTER is pressed by the user. Here, the intro and exit text is implemented, but your submission does not need to include this. Your design does not have to look exactly like this.
$ python3 design-ww.py
Welcome to Word Warp v0.1!
Find as many words as you can from the given letters.
Only words of 4 or more letters count!
Longer words are worth more points:
4 letters.....4 points
5 letters.....5 points
6 letters.....6 points
Hit the ENTER key if you want to quit.
Enter WW to shuffle the given letters (and lose 5 points).
Your word: tacos
Invalid word! Try again
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Your word: pudding
Invalid word! Try again
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Your word: asrugh!!
Invalid word! Try again
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Your word:
Quitting...
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Game OVER
Your final score was: 0
Possible words: []