python example of function with docstring that does selfcontained unit tests

function.py

def suma(a: int = None, b: int = None) -> int:
    """ sums two given integers

    Args:
        a: int
        b: int
    return:
        int

    >>> suma(2,4)
    6

    >>> suma(2)
    Traceback (most recent call last):
    Exception: parameters are not given

    >>> suma()
    Traceback (most recent call last):
    Exception: parameters are not given
    """
    if not (a and b):
        raise Exception("parameters are not given")
        
    return a + b
    
    
    
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$ python -m doctest function.py