When working with Python 2.7, you may come across a situation where you need to assign the result of extending a list to a variable. This can be a bit tricky, as the behavior of the extend method differs between Python 2 and Python 3. In this article, we will explore three different ways to solve this problem.

Solution 1: Using the plus operator

One way to solve this problem is by using the plus operator to concatenate the two lists. Here’s an example:

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

In this solution, we simply concatenate the two lists using the plus operator. This works in both Python 2 and Python 3, making it a reliable solution.

Solution 2: Using the append method

Another way to solve this problem is by using the append method to add the elements of the second list to the first list. Here’s an example:

list1 = [1, 2, 3]
list2 = [4, 5, 6]
for element in list2:
    list1.append(element)
print(list1)  # Output: [1, 2, 3, 4, 5, 6]

In this solution, we iterate over the elements of the second list and append each element to the first list. This solution also works in both Python 2 and Python 3.

Solution 3: Using the extend method with a temporary list

The third solution involves using the extend method with a temporary list. Here’s an example:

list1 = [1, 2, 3]
list2 = [4, 5, 6]
temp_list = []
temp_list.extend(list1)
temp_list.extend(list2)
print(temp_list)  # Output: [1, 2, 3, 4, 5, 6]

In this solution, we create a temporary list and use the extend method to add the elements of both lists to it. Finally, we print the temporary list, which contains the desired result. This solution is also compatible with both Python 2 and Python 3.

After considering these three solutions, the best option depends on the specific requirements of your code. If you prefer a concise solution, Solution 1 using the plus operator is a good choice. However, if you need to preserve the original lists or want to perform additional operations on them, Solution 2 or Solution 3 may be more suitable. Ultimately, the decision should be based on the context and needs of your project.