   @spec new(Enum.t) :: t
   def new(enumerable)
 
-  def new(%__MODULE__{} = mapset), do: mapset
+  def new(%__MODULE__{} = map_set), do: map_set
   def new(enumerable) do
     map =
       enumerable

  end

  @doc """
  Checks if `set1`'s members are all contained in `set2`.

  This function checks if `set1` is a subset of `set2`.

  ## Examples


      iex> MapSet.new
      #MapSet<[]>

  A set can contain any kind of elements, and elements in a set don't have to be
  of the same type. By definition, sets can't contain duplicate elements: when
  inserting an element in a set where it's already present, the insertion is
  simply a no-op.

      iex> map_set = MapSet.new
      iex> MapSet.put(map_set, "foo")
      #MapSet<["foo"]>
      iex> map_set |> MapSet.put("foo") |> MapSet.put("foo")
      #MapSet<["foo"]>

  A `MapSet` is represented internally using the `%MapSet{}` struct. This struct
