doctest.py

def square_number(list_of_number):
    """
    @param list_of_number: a given list of integer number
    @return: list of square number

    >>> square_number([1, 2, 3, 4])
    [1, 4, 9, 16]

    >>> square_number([10, 20, 30])
    [100, 400, 900]
    """

    return [num ** 2 for num in list_of_number]


if __name__ == '__main__':
    import doctest
    doctest.testmod()