>>> numbers = [1 , 2, 3, 4, 4, 6] # a normal python list
>>> numbers[4] = 5 # replace the redundant item (5th item)
>>> numbers
[1, 2, 3, 4, 5, 6]
>>> l= ['X','X',52,39,81,12,'X',62,94]
>>>
>>> l = list(map(lambda x:0 if x=="X" else x,l))
>>> l
[0, 0, 52, 39, 81, 12, 0, 62, 94]