solution: Since $f(2) = 6$, we have $f^{-1}(6)=2$. (Note that the hypothesis that $f$ has an inverse implies that there are no other values of $x$ with $f(x) = 6$.)  Similarly, $f(1) =2$ implies $f^{-1}(2)=1$.   So $f^{-1}(f^{-1}(6))=f^{-1}(2)=\boxed{1}$.
prompt.content: <|im_start|>system
  You are a helpful assistant.<|im_end|>
  <|im_start|>user
  Suppose that $f$ is a function and $f^{-1}$ is the inverse of $f$.  If $f(1)=2$, $f(2) = 6$, and $f(3)=5$, then what is $f^{-1}(f^{-1}(6))$?
  Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
  <|im_start|>assistant
  
prompt.role: user
extra_info.answer: 1
extra_info.question: Suppose that $f$ is a function and $f^{-1}$ is the inverse of $f$.  If $f(1)=2$, $f(2) = 6$, and $f(3)=5$, then what is $f^{-1}(f^{-1}(6))$?
extra_info.split: test