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How to merge two lists in Python

How to merge two lists in Python.

Here's a step-by-step tutorial on how to merge two lists in Python.

1: Create two lists

First, let's create two separate lists that we want to merge. For example, let's create list1 and list2:

list1 = [1, 2, 3]
list2 = [4, 5, 6]

2: Using the "+" operator

One of the simplest ways to merge two lists in Python is by using the "+" operator. You can simply use the "+" operator to concatenate the two lists. Here's an example:

merged_list = list1 + list2
print(merged_list)

Output:

[1, 2, 3, 4, 5, 6]

3: Using the extend() method

Another way to merge two lists is by using the extend() method. The extend() method adds all the elements from one list to another list. Here's an example:

list1.extend(list2)
print(list1)

Output:

[1, 2, 3, 4, 5, 6]

4: Using the append() method in a loop

If you have multiple lists that you want to merge, you can use a loop and the append() method to merge them one by one. Here's an example:

list1 = [1, 2, 3]
list2 = [4, 5, 6]
list3 = [7, 8, 9]

merged_list = []
for lst in [list1, list2, list3]:
merged_list.extend(lst)

print(merged_list)

Output:

[1, 2, 3, 4, 5, 6, 7, 8, 9]

5: Using the itertools module

The itertools module in Python provides a dedicated function called chain() that can be used to merge multiple lists. Here's an example:

import itertools

list1 = [1, 2, 3]
list2 = [4, 5, 6]
list3 = [7, 8, 9]

merged_list = list(itertools.chain(list1, list2, list3))
print(merged_list)

Output:

[1, 2, 3, 4, 5, 6, 7, 8, 9]

That's it! You now know multiple ways to merge two or more lists in Python. Choose the method that suits your requirements best.