Help in python please.

Using a USet, implement a Bag. A Bag is like a USetit supports the add(x ), remove(x ) and nd(x ) methodsbut it allows duplicate elements to be stored. The nd(x ) operation in a Bag returns some element (if any) that is equal to x . In addition, a Bag supports the nd all(x ) operation that returns a list of all elements in the Bag that are equal to x .