how to define the length of a list in python code example

Example 1: python get the length of a list

studentGrades = [9.1, 8.8, 10.0, 7.7, 6.8, 8.0, 10.0, 8.1, 10.0, 9.9]
print(len(studentGrades))

Example 2: python list of size

li = [None] * 5 # [None, None, None, None, None]
li = [0] * 5 # [0, 0, 0, 0, 0]