Check for Duplicates in Python Lists | Programming Tutorial

Introduction

In Python, a list is a collection of items that are ordered and changeable. Sometimes, we need to check if a list contains duplicate values. In this challenge, you will write a function that checks if a list has any duplicates.

Skills Graph

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Check for Duplicates in a List

Problem

Write a Python function called has_duplicates(lst) that takes a list as an argument and returns True if the list contains any duplicates, and False otherwise.

To solve this problem, you can use the following steps:

Use the set() function to remove duplicates from the list.
Compare the length of the original list with the length of the set. If they are the same, then there are no duplicates. If they are different, then there are duplicates.

Example

x = [1, 2, 3, 4, 5, 5]
y = [1, 2, 3, 4, 5]
print(has_duplicates(x)) ## True
print(has_duplicates(y)) ## False

Summary

In this challenge, you learned how to check for duplicates in a list using Python. You can use the set() function to remove duplicates and compare the length of the original list with the length of the set to determine if there are any duplicates.

Check for Duplicates in a List | Challenge