""" experiment with tracing
"""


def f(n):
    """explore composition, 1"""
    return n + 1


def g(m):
    """explore composition, 2"""
    return f(m) + 1


def fibonacci(n):
    """explore fibonacci"""
    if n < 2:
        return n
    else:
        return fibonacci(n - 1) + fibonacci(n - 2)


if __name__ == "__main__":
    fibonacci(4)