Inserting data into a nested list in Python

I have a list like this:

list = [['a1', 'a2', 'a3'], ['b1', 'b2', 'b3'], ['c1', 'c2', 'c3']]

I am trying to return a list like this where ' newdata' is added into every row in the seco开发者_JS百科nd "column":

list = [['a1', 'a2 newdata', 'a3'], ['b1', 'b2 newdata', 'b3'], ['c1', 'c2 newdata', 'c3']]

What is best way to do this?

Considering ' newdata' is a string, else you ll have to use str()

for item in list:
        item[1] += ' newdata'

To iterate over your list you can do something like this:

for element in my_list:
  print element

And it will print all the elements in your list. It appears that every element inside your nested list is a string, therefore, to add a string to the 2nd element of that nested list you'd need to:

for element in my_list:
  print element[1] += ' newdata'

Remember, index starts at 0. if 'newdata' isn't a string you'll need to use this as:

for element in my_list:
  print element[1] += ' ' + str(newdata)

This page might have more useful information on how to iterate over your list:

• https://wiki.python.org/moin/ForLoop