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The first example is used to explain what a tensor product of 2 graphs is.

The second example was used to show how colouring the tensor product may actually be useful.

I thought the second example was a little more complex (primarily because it requires the connection of incompatible nodes, as opposed to the more straightforward pairing of compatible nodes), so having a different, more straight forward example to just explain tensor products was helpful.

Also, having 2 different unrelated examples for the same thing can definitely help with understanding the underlying property/theorem.

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