def never_using_comprehensions():
    squares = {}
    for i in range(10):
        squares[i] = i * i
    print(squares)

def using_comprehensions():
    odd_squares = {i: i * i for i in range(10)}
    print(odd_squares)

def various_comprehensions_examples():
    # dictionary comprehension example
    dict_comp = {i: i * i for i in range(10)}
    print(dict_comp)

    # list comprehension example
    list_comp = [x*x for x in range(10)]
    print(list_comp)

    # set comprehension example
    set_comp = {i%3 for i in range(10)}
    print(set_comp)

    # generator comprehension example
    gen_comp = {2*x+5 for x in range(10)}
    print(gen_comp)

# Calling all the functions
never_using_comprehensions()
using_comprehensions()
various_comprehensions_examples()