Using itertools and generators

example3.py

import itertools
from memory_profiler import profile

@profile
def my_func():
    a = [1] * (10 ** 6)
    # A generator adds nothing to memory as each index is loaded
    # on the fly
    b = (2 for _ in range(2 * 10 ** 7))
    # we discard the first 199999 from the generator using itertools
    # and then call next() to access the 200000th which is what we want
    c = next(itertools.islice(b, 199999))
    return a.append(c)

if __name__=="__main__":
    my_func()