Here is the explanation of the keys used for grading reading quizzes.
In addition, if your work is late, then you will get only 2/3 of the score listed below.

{{{#!highlight python numbers=off

'AA': (150, 'Your answer accepted as one of the best answers'),
'UV': (125, 'Your answer upvoted by instructor'),
'PP': (100, 'Practically perfect'),
'PR': (100, 'Practice question'),
'IA': (90, 'Incorrect or incomplete answer'),
'MU': (90, 'Missed quiz, and made it up later by submitting a report'),
'NW': (0, 'No work submited'),

}}}