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Python

Posted by Benjamin Hedgepeth
Benjamin Hedgepeth
5,672 Points

Lists and the Append() function in Python

What is the meaning of 'None' when appending one list object to another list object?

>>> list_one = ["abc", "def", "ghi"]
>>> list_two = ["jkl", "mno", "pqr"]
>>> print(list_one.append(list_two))
None

>>> print(list_one)
['abc', 'def', 'ghi', ['jkl', 'mno', 'pqr']]

1 Answer

Sean Pomerantz
Sean Pomerantz
1,722 Points
Sean Pomerantz
Sean Pomerantz
1,722 Points

The function .append() simply adds an item to the end of a list and does not return a value. A function that does not return a value returns "None".

Nikolai Montesclaros
Nikolai Montesclaros
11,928 Points
Nikolai Montesclaros
Nikolai Montesclaros
11,928 Points

Sean is correct and to just to expand, its really the print statement that is returning None and has nothing to do with appending to your list.