__init__.py 文件源码

def is_closable_iterator(obj):

    # Not an iterator.
    if not is_iterator(obj):
        return False

    # A generator - the easiest thing to deal with.
    import inspect
    if inspect.isgenerator(obj):
        return True

    # A custom iterator. Look for a close method...
    if not (hasattr(obj, 'close') and callable(obj.close)):
        return False

    #  ... which doesn't require any arguments.
    try:
        inspect.getcallargs(obj.close)
    except TypeError:
        return False
    else:
        return True