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Introduction to Lists in Python

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Introduction to Lists in Python

Lists are one of the most versatile and commonly used data structures in Python. They are used to store collections of items, which can be of different types, and are mutable, meaning their elements can be changed after they are created.

Lists are created by placing comma-separated values inside square brackets []. Here's the syntax:

# Creating a list
my_list = [1, 'apple', 3.14, 'python']

You can access elements of a list using indexing. Python uses zero-based indexing, meaning the first element has an index of 0, the second element has an index of 1, and so on. Negative indexing can also be used to access elements from the end of the list.

# Accessing elements of a list
print(my_list[0])  # Output: 1
print(my_list[1])  # Output: 'apple'
print(my_list[-1]) # Output: 'python'

Lists in Python support various operations such as concatenation, repetition, slicing, and more.

Here's a quick summary of some common list operations:

  • Concatenation: Combining two or more lists using the + operator.
  • Repetition: Replicating a list using the * operator.
  • Slicing: Extracting a portion of a list using the slicing notation [start:end:step].
  • Appending: Adding an item to the end of a list using the append() method.
  • Inserting: Inserting an item at a specified position using the insert() method.
  • Removing: Removing the first occurrence of an item using the remove() method.
  • Pop: Removing and returning an item from a specified position using the pop() method.
  • Length: Getting the number of items in a list using the len() function.

Lists are versatile and can be used in various programming scenarios, making them an essential part of Python programming.

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