def __init__(self, block=None, **kwargs):
        if block is None:
            raise ImproperlyConfigured("BlockField was not passed a 'block' object")
        self.block = block

        if 'widget' not in kwargs:
            kwargs['widget'] = BlockWidget(block)

        super(BlockField, self).__init__(**kwargs)
dataset/ETHPy150Open torchbox/wagtail/wagtail/wagtailcore/blocks/base.py/BlockField.__init__/original