1 #!/usr/bin/python
 2 import sys
 3 
 4 def str2listuniq(s):
 5     l = []
 6     for c in list(s):
 7         if c not in l:
 8             l.append(c)
 9     return l
10 
11 def insert_c2s(s, c):
12     l = []
13     i = 0
14     while i <= len(s):
15         start = s[0:i]
16         end   = s[i:]
17         e     = start + c + end
18         l.append(e)
19         i += 1
20     return l
21 
22 def list2allperms(l):
23     l_final = [l[0]]
24     for c in l[1:]:
25         l_cell = []
26         for s in l_final:
27             l_cell.extend(insert_c2s(s, c))
28         l_final = l_cell
29     return l_final
30 
31 def main(argc, argv):
32     if argc != 2:
33         sys.stderr.write("Usage: %s <string>\n" % argv[0])
34         sys.stderr.write(" e.g.: %s \"abc\"\n" % argv[0])
35         return -1
36 
37     if len(argv[1]) == 0:
38         sys.stderr.write("Oops, string is blank\n")
39         return -1
40 
41     l_input = str2listuniq(argv[1])
42     l_final = list2allperms(l_input)
43     if len(l_final) <= 24:
44         print ‘ ‘.join(l_final)
45     else:
46         print ‘ ‘.join(l_final[0:5]) + " ... " + l_final[-1]
47     print "\nThe total number of all permutation is %d" % len(l_final)
48 
49     return 0
50 
51 if __name__ == ‘__main__‘:
52     argc, argv = len(sys.argv), sys.argv
53     sys.exit(main(argc, argv))

$ ./foo.py a
a

The total number of all permutation is 1

$ ./foo.py ab
ba ab

The total number of all permutation is 2

$ ./foo.py abc
cba bca bac cab acb abc

The total number of all permutation is 6

$ ./foo.py abcd
dcba cdba cbda cbad dbca bdca bcda bcad dbac bdac badc bacd dcab cdab cadb cabd dacb adcb acdb acbd dabc adbc abdc abcd

The total number of all permutation is 24

$ ./foo.py abcde
edcba decba dceba dcbea dcbae ... abcde

The total number of all permutation is 120