   @doc """
   Puts a value in a nested structure.
 
-  Uses the `Access` protocol to traverse the structures
+  Uses the `Access` module to traverse the structures
   according to the given `keys`, unless the `key` is a
   function. If the key is a function, it will be invoked
   as specified in `get_and_update_in/3`.

  @doc """
  Updates a key in a nested structure.

  Uses the `Access` protocol to traverse the structures
  according to the given `keys`, unless the `key` is a
  function. If the key is a function, it will be invoked
  as specified in `get_and_update_in/3`.

      27

  In case any of entries in the middle returns `nil`, `nil` will be returned
  as per the Access module:

      iex> users = %{"john" => %{age: 27}, "meg" => %{age: 23}}
      iex> get_in(users, ["unknown", :age])
