How do you remove duplicate elements from a list in Python?

Question

Aryan Kumar · Answer

There are several ways to remove duplicates from a list in Python. Here are some of the most common methods:
Using the set() method
The set() method creates a new set from the elements of a list. Sets do not allow duplicate elements, so the new set will only contain the unique elements from the original list. To use this method, you would simply pass the list to the
set() method and then convert the resulting set back to a list.
Python
def remove_duplicates_set(list1):
    unique_list = set(list1)
    unique_list = list(unique_list)
    return unique_list
list1 = [1, 2, 3, 4, 5, 1, 2, 3]
unique_list = remove_duplicates_set(list1)
print(unique_list)
Using list comprehension
You can also use list comprehension to remove duplicates from a list. List comprehension is a concise way to create a new list from an existing list. To use list comprehension to remove duplicates, you would simply iterate through the original list and add each element to the new list only if it is not already in the new list.
Python
def remove_duplicates_list_comprehension(list1):
    unique_list = []
    for item in list1:
        if item not in unique_list:
            unique_list.append(item)
    return unique_list
list1 = [1, 2, 3, 4, 5, 1, 2, 3]
unique_list = remove_duplicates_list_comprehension(list1)
print(unique_list)
Using the in and 
not in operators
You can also use the in and not in operators to remove duplicates from a list. The
in operator checks whether an element is in a list, and the not in operator checks whether an element is not in a list. To use these operators to remove duplicates, you would simply iterate through the original list and add each element to the new list only if it is not already in the new list.
Python
def remove_duplicates_in_not_in(list1):
    unique_list = []
    for item in list1:
        if item not in unique_list:
            unique_list.append(item)
    return unique_list
list1 = [1, 2, 3, 4, 5, 1, 2, 3]
unique_list = remove_duplicates_in_not_in(list1)
print(unique_list)
These are just a few of the ways to remove duplicates from a list in Python. The best method to use will depend on the specific situation.

forum

How do you remove duplicate elements from a list in Python?

Utpal Vishwas

Can you answer this question?

1 Answers

Liked By