Python: How do i sort Names in a text file alphabetically?

Question

my questions is, how to i sort by the 1st letter of the person's name in a text file(A at the top going to Z at the bottom). I use python 3.4.3.

I have a text file containing names and scores: = ('test', ' ', 1) I've tried the code below however it doesn't seem to sort alphabetically.

age = class number

file = open(str(age) + ".txt" , "a")
file.write(name + " " + " {}\n".format(score))
f = open(str(age) + ".txt" , "r")
lines = f.readlines()
f.close()
lines.sort()
f = open(str(age) + ".txt" , "w")
for line in lines:
    f.write(line)
f.flush()
f.close()
print(lines)

Answer 1

The problem is probably in your file. The code you posted works fine for a .txt file such as:

Dave = 12
Peter = 5
Agnes = 4
Charles = 10
Mary = 8

Please post your file.