   @doc """
   Merges two maps into one.
 
-  All keys in `map2` will be added to `map1`, overriding any existing one.
+  All keys in `map2` will be added to `map1`, overriding any existing one
+  (i.e., the keys in `map2` "have precedence" over the ones in `map1`).
 
   If you have a struct and you would like to merge a set of keys into the
   struct, do not use this function, as it would merge all keys on the right

  @doc """
  Returns and removes the value associated with `key` in `map`.

  ## Examples

      iex> Map.pop(%{a: 1}, :a)

  def fetch(map, key), do: :maps.find(key, map)

  @doc """
  Fetches the value for a specific `key` in the given `map`, erroring out if
  `map` doesn't contain `key`.

  If `map` contains the given `key`, the corresponding value is returned. If
  `map` doesn't contain `key`, a `KeyError` exception is raised.

  ## Examples

