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Python Set intersection_update() Method (with Examples)

Last Updated : December 11, 2025

Python Set intersection_update() Method

The intersection_update() is an inbuilt method of the set class that is used to update the original set with the common elements which exist in all sets i.e., we can say intersection_update() is used to remove unwanted elements (which are not available in all sets).

Syntax

The following is the syntax of intersection_update() method:

set1.intersection_update(set1, set2, set3, ...)

Parameter(s):

The following are the parameter(s):

• set1 – It represents the set to be compared with this set.
• set2, set3, ... – These are optional sets, we can provide multiple sets to be compared.

Return Value

The return type of this method is <class 'NoneType'>, it returns nothing.

Example 1: Use of Set intersection_update() Method

# declaring the sets
cars_1 = {"Porsche", "Audi", "Lexus"}
cars_2 = {"Porsche", "Mazda", "Lincoln"}

# before method call 
print("Before intersection_update() method call...")
print("cars_1:", cars_1)
print("cars_2:", cars_2)

# intersection_update() method call
cars_1.intersection_update(cars_2)

# printing the set after method call
print("After intersection_update() method call...")
print("cars_1:", cars_1)
print("cars_2:", cars_2)

Output

Before intersection_update() method call...
cars_1: {'Lexus', 'Porsche', 'Audi'}
cars_2: {'Lincoln', 'Porsche', 'Mazda'}
After intersection_update() method call...
cars_1: {'Porsche'}
cars_2: {'Lincoln', 'Porsche', 'Mazda'}

Example 2: Use of Set intersection_update() Method

# declaring the sets
x = {"ABC", "PQR", "XYZ"}
y = {"ABC", "PQR", "XYZ"}
z = {"DEF", "MNO", "ABC"}

# printing the results
print("x:", x)
print("y:", y)
print("z:", z)

# printing the common elements
x.intersection_update(y,z)
print("x: ",x)

Output

x: {'XYZ', 'PQR', 'ABC'}
y: {'XYZ', 'PQR', 'ABC'}
z: {'MNO', 'ABC', 'DEF'}
x:  {'ABC'}