# Double the input
def double_it(x):
    return x * 2


def another_double_it(x):
    print(x * 2)


def foo(x):
    """
    this is my docstring
    it can take up multiple lines
    this is a horrible docstring because it doesn't describe how the function behaves
    """
    return x * 2
    
def foo(x):
    """
    Doubles input.
    
    Args:
        x: value to be doubled

    Returns:
        Doubled value
    """
    return x * 2 


def lorenz(velocity):
    """ Compute lorenz factor """
    return 1 / (1 - (velocity ** 2) / (300000000 ** 2)) ** 0.5