My neighbor gave me a bag of these… anyone know what they are? How do you eat them?

Củ ấu also known as water caltrop, devil pod, buffalo nut, horn nuts, ling nuts, bat nut, mustache nut or water chestnut. This is a  fruit and also nut forming from the water caltrop plant which is a water weed that blocks dense waterways. The  fruits are boiled and the starchy inner meat is eaten.

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