How is mango a dicot(as told in the video lesson) when its seed is single?

How is mango a dicot(as told in the video lesson) when its seed is single? Please explain with a diagram.

Dicot plant means there are two cotyledons in the seed of the plant. It is not the number of seeds which is relevant.
The below figure shows the difference between a monocot seed and a dicot seed.
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