The difference_update() method computes the difference between two sets (A - B) and updates set A with the resulting set.
Example
# sets of numbers
A = {1, 3, 5, 7, 9}
B = {2, 3, 5, 7, 11}
# computes A - B and updates A with the resulting set
A.difference_update(B)
print('A = ', A)
# Output: A =  {1, 9}
difference_update() Syntax
The syntax of the difference_update() method is:
A.difference_update(B)
Here, A and B are two sets.
difference_update() Parameter
The difference() method takes a single argument:
- B - a set whose items won't be included in the resulting set
 
difference_update() Return Value
The difference_update() doesn't return any value.
Example: Python difference_update()
A = {'a', 'c', 'g', 'd'}
B = {'c', 'f', 'g'}
print('A before (A - B) =', A)
A.difference_update(B)
print('A after (A - B) = ', A)
Output
Original Set = {'a', 'g', 'c', 'd'}
A after (A - B) =  {'a', 'd'}
In the above example, we have used the difference_update() method to compute the difference between two sets A and B and update set A with the resulting set.
Here, A.difference_update(B) performs A - B and updates set A with value {'a', 'd'}
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