Day 6: Python Syntax: Basic Concepts — List Operation in detail

Admin June 20, 2025

Python in 30 Days: A Practical and Theoretical Approach for Beginner.

A list is one of the most commonly used data structures in Python.

Table of Contents

List Operations:

Concatenation:

You can concatenate two lists using the + operator.

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

Repetition:

You can repeat a list using the * operator.

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

List comprehension:

A concise way to create lists.

squares = [x ** 2 for x in range(5)]
print(squares)  
# Output: [0, 1, 4, 9, 16]

Nested Lists:

Lists can contain other lists as elements.

nested_list = [[1, 2], [3, 4], [5, 6]]
print(nested_list[0])  
# Output: [1, 2]
print(nested_list[0][1]) 
 # Output: 2

append(): Adds an item to the end of the list.
insert(): Adds an item at a specified index.
remove(): Removes the first occurrence of an item.
pop(): Removes and returns an item at a given index (default is the last item).
sort(): Sorts the list in place (alphabetically or numerically).
reverse(): Reverses the list.
clear(): Removes all items from the list.