A set can be copied using = operator in Python. For example:
numbers = {1, 2, 3, 4}
new_numbers = numbers
The problem with copying the set in this way is that if you modify the numbers set, the new_numbers set is also modified.
numbers = {1, 2, 3, 4}
new_numbers = numbers
new_numbers.add(5)
print('numbers: ', numbers)
print('new_numbers: ', new_numbers)
Output
numbers: {1, 2, 3, 4, 5}
new_numbers: {1, 2, 3, 4, 5}
However, if you need the original set to be unchanged when the new set is modified, you can use the copy() method.
The syntax of copy() is:
set.copy()
copy() Parameters
It doesn't take any parameters.
Return Value from copy()
The copy() method returns a shallow copy of the set.
Example 1: How the copy() method works for sets?
numbers = {1, 2, 3, 4}
new_numbers = numbers.copy()
new_numbers.add(5)
print('numbers: ', numbers)
print('new_numbers: ', new_numbers)
Output
numbers: {1, 2, 3, 4}
new_numbers: {1, 2, 3, 4, 5}