_Constant functors._

Let \$$C\$$ and \$$D\$$ be categories. Given any object \$$d\$$ in \$$D\$$, we can define the _constant functor_ \$$K_d: C \rightarrow D\$$ on \$$d\$$. This functor sends _every_ object \$$C\$$ to \$$d \in Ob\ D\$$, and _every_ morphism of \$$C\$$ to the identity morphism on \$$d\$$.

(a) Take the set \$$B\$$ = {\$$T,F\$$}. Show that the constant functor \$$K_B: Set \rightarrow Set\$$ obeys the two functor laws: preservation of composition and preservation of identities.

(b) Implement in Haskell the constant functor on the type Bool.

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