i = 0seq = ['one', 'two', 'three']for element in seq:    PRint i, seq[i]    i += 1#0 one#1 two#2 threeprint '============'seq = ['one', 'two', 'three']for i, element in enumerate(seq):    print i, seq[i]    print '============'for i,j in enumerate('abc'):    print i,j#0 a#1 b#2 cprint '============'def _treatment(pos, element):    return '%d: %s' %(pos, element)seq = ['one', 'two', 'three']print [_treatment(i, e1) for i, e1 in enumerate(seq)]