Python List Operations Explained

You can use + and * operation to extend a list.

List Add (+) Operation

Add (+) operator is used to combine (concatenates) several lists into a single list. It is similar to list.extend() method.

Example:

list1 = [1, 2]
list2 = [3, 4]
list3 = [5, 6]
combined_list = list1 + list2 + list3
print(combined_list)  # Output: [1, 2, 3, 4, 5, 6]

List Multiply (*) Operation

Multiply (*) operator will create a new list by repeating the elements of the original list a specified number of times.

Example:

original_list = [1, 2, 3]
replicated_list = original_list * 3
print(replicated_list)
# Output: [1, 2, 3, 1, 2, 3, 1, 2, 3]

Caution

This replication is a shallow copy. Especially, if the elements in list are mutable objects (like lists or dictionaries).

Exampe:

nested_list = [[1, 2], [3, 4]]
replicated_nested_list = nested_list * 2
replicated_nested_list[0][0] = 5
print(replicated_nested_list)
# Output: [[5, 2], [3, 4], [5, 2], [3, 4]]