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Python

問題文からいまいち仕様が読み取りにくい。こんなのでいいのかな。

import operator

def flatten(obj):
    """
    flatten specified nested list.

    >>> flatten([1, [2, 3, 4], 5, [[6], [7, 8], 9], 10])
    [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
    """
    if isinstance(obj, list):
        return reduce(operator.add, (flatten(elem) for elem in obj), [])
    else:
        return [obj]

def print_atoms(obj):
    """
    print conent of ntested list
    
    >>> print_atoms([1, [2, 3, 4], 5, [[6], [7, 8], 9], 10])
    1, 2, 3, 4, 5, 6, 7, 8, 9, 10
    """
    print ', '.join(str(elem) for elem in flatten(obj))

def is_all_int(obj):
    """
    return if specified object consists of int and list only.

    >>> is_all_int([1, 2, [], 3])
    True

    >>> is_all_int([1, '2', [3]])
    False
    """
    return all(isinstance(e, int) for e in flatten(obj))

def _test():
    import doctest
    doctest.testmod()

if __name__ == '__main__':
    _test()