fname = raw_input('Enter file name: ') fhand = open(fname) c = dict() for line in fhand: if not line.startswith('From ') : continue pieces = line.split() time = pieces[5] parts = time.split(':') hour = parts[0] c[hour] = c.get(hour,0) + 1 lst = list() for key in c: value = c[key] lst.append( (value, key) ) lst.sort() for value, key in lst: print key, value