In the Category of $\mathbf{ Set } $ is "the product of an empty set of sets a one-element set"?

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I was reading these notes on Category Theory and it said (paraphrased to add context):

Exercise 4: Explain why in Set (the Category of Sets), the product of an empty set of sets is a one-element set.

which I think is incorrect. The product of two empty sets (or any number) is empty because we are considering:

$$ \emptyset \times \emptyset = \{ (a,b) : a \in \emptyset, b \in \emptyset \} = \emptyset$$

where $a \in \emptyset , b \in \emptyset$ are false, so the above is the $\emptyset$ which is NOT a one element set (its a zero element set).

This should be trivial so I am assuming I am somewhere mis reading the natural language of the exercise. Someone help me catch where is it? i.e whats being asked and what the answer is?