Question: In scheme/ racket, write a function (seen x) that takes a single argument x and return #t if it has been previously called with the

In scheme/ racket, write a function (seen x) that takes a single argument x and return #t if it has been previously called with the same argument and #f otherwise.

Hint: You may use a global variable if you like, but a solution that does not use global state is possible.

Example: (begin (seen 5) (seen 5)) will return #t

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