sorting - Python : Displaying a sorted dictionary by more than one condition -

what want code sum parcial grades of each student , return final grade, ordering them grade, and if students same grade, display high number student first.

my code:

nice={}  try:      open('grades.txt') file:         data = file.readlines()  except ioerror ioerr:     print(str(ioerr))   each_line in data:     (number, grade) = each_line.split()     if number not in nice:         nice[number]=0     nice[number]+=int(grade)   in sorted(nice, key=lambda n: (-nice[n],n)):     print(i,nice[i]) 

my input: file: "grades.txt"

10885 10 70000 6 70000 10 60000 4 70000 4 60000 4 10885 10 60001 5 60002 8 60003 8 

my output:

10885 20 70000 20 60000 8 60002 8 60003 8 60001 5 

as can see, i've found way sum each parcial grade final grade , display them grades, yet i've not figured out how implement other condition, getting desired output:

10885 20 70000 20 60003 8 60002 8 60000 8 60001 5 

since students 60000,60002,60003 have same grade, should displayed above, 60003>60002>60000.

its helpful try , think of different (ie condition inverted)

sorted(nice.items(), key=lambda itm: map(int,itm[::-1]),reverse=true) 

or in python 3

sorted(nice.items(), key=lambda v: (int(v[1]),int(v[0])),reverse=true) 

or

sorted(nice.items(), key=lambda itm: list(map(int,itm[::-1])),reverse=true) 

should work python2 or 3

python3.4.3

>>> nice {'60000': '8', '60001': '5', '70000': '20', '60003': '8', '10885': '20', '60002': '8'} >>> sorted(nice.items(), key=lambda itm: list(map(int,itm[::-1])),reverse=true) [('70000', '20'), ('10885', '20'), ('60003', '8'), ('60002', '8'), ('60000', '8'), ('60001', '5')]