nl: result of the call to the function _ with an argument string 'Tue' for 1, result of the call to the function _ with an argument string 'Wed' for 2, result of the call to the function _ with an argument string 'Thu' for 3, result of the call to the function _ with an argument string 'Fri' for 4, result of the call to the function _ with an argument string 'Sat' for 5, and result of the call to the function _ with an argument string 'Sun' for 6. WEEKDAYS_REV is an dictionary with 7 entries: 0 for 'monday', 1 for 'tuesday', 2 for 'wednesday', 3 for 'thursday', 4 for 'friday', 5 for 'saturday' and 6 for 'sunday'.
code: WEEKDAYS_REV = { 'monday' : 0 , 'tuesday' : 1 , 'wednesday' : 2 , 'thursday' : 3 , 'friday' : 4 , 'saturday' : 5 , 'sunday' : 6 }