Four ways of generating the Fibonacci sequence in Python

fibonacci.py

# Tail recursive fibonacci
def get_fib(final, num=1, current=1, prev=0):
    if final == 0:
        return 0
    if num < final:
        prev, current = current, prev + current
        return get_fib(final, num + 1, current, prev)
    else:
        return current


# Head recursive fibonacci
def head_fib(num):
    if num < 2:
        return num
    return head_fib(num - 1) + head_fib(num - 2)


# Generator fibonacci
def fibonacci():
    a, b = 0, 1
    while True:
        yield a
        a, b = b, a + b


# Primes generator
def primes():
    num = 2
    while True:
        for divisor in range(2, num):
            if num % divisor == 0:
                num += 1
                break
        else:
            yield num
            num += 1