A List is a sequence data type in Python. It is a comma separated list of elements, not necessarily of same type, included in square brackets ([ ]). List is an ordered collection. Individual element in a List object can be accessed by a zero based index.
list1 = ['physics', 'chemistry', 1997, 2000]; list2 = [1, 2, 3, 4, 5 ]; list3 = ["a", "b", "c", "d"]
A List object with no element between square brackets is a null list.
list1 =