Create a bag:
bag = fromList ['a', 'b', 'b']Count the number of copies of a value in a bag:
count 'b' bag == 2Insert values into a bag:
insert 1 'a' bag == fromList ['a', 'a', 'b', 'b']Remove values from a bag:
remove 1 'b' bag == fromList ['a', 'b']