message: Make fn fibonacci() public
diff: @@ -6,7 +6,7 @@ I'll assume that we have a crate, `mycrate`, whose `lib.rs` contains the followi
  ```rust
  #[inline]
  -fn fibonacci(n: u64) -> u64 {
  +pub fn fibonacci(n: u64) -> u64 {
  match n {
  0 => 1,
  1 => 1,
  