Returns the values in array1 and not in array2.
difference( array1, array2, … )
array1: (Any Type Array) Initial array of values.
array2: (Any Type Array) Array of values to remove from array1.
Any Type Array
If all values are removed from array1, an empty list is returned.
difference({1, 2, 3, 4}, {3, 4})
returns 1, 2