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pythonlistappendtuplessublist

How to append one value to every tuple within a list?

How to append 1 value to every tuple within a list?

 tuple_list = [('a','b'),('c','d'),('e','f')]
 value = 111


 Desired_List = [(111,'a','b'),(111,'c','d'),(111,'e','f')]

I've tried the following: 

   for x in tuple_list:
        x.append(111)

   for x in tuple_list:
        x + '111'

I prefer sublists over tuples, so is there anyway to change the tuples to sublists as well?

Notes: It actually doesn't matter whether the 111 is in the first index or the last index of the tuple.

Solution

  • You can use a list comprehension to do both of the things you're looking to do.

    To prefix:

    desired_list = [[value]+list(tup) for tup in tuple_list]

    To suffix:

    desired_list = [list(tup)+[value] for tup in tuple_list]

    The list() call transforms each tuple into a list, and adding another list which contains only value adds that value to each list once it has been created.