How can a mechanism be implemented to sequentially obtain random or pre-defined values?

To sequentially obtain random or predefined values in Python, you can use generators or iterators.

Example with predefined values:

def predefined_sequence():
    values = [10, 20, 30, 40]
    for v in values:
        yield v

seq = predefined_sequence()
print(next(seq))  # 10
print(next(seq))  # 20

Example with sequential random values:

import random

def random_sequence(n):
    for _ in range(n):
        yield random.randint(1, 100)

rand_seq = random_sequence(5)
for val in rand_seq:
    print(val)

Thus, generators allow for an easy implementation of a mechanism to sequentially obtain values without the need to store the entire sequence in memory.