   end
 
   @doc """
-  Returns a set combining the two input sets.
+  Returns a set containing all members of `set1` and `set2`.
 
   ## Examples
 

    target(set1).union(set1, set2)
  end

end
  end

  @doc """
  Returns the number of elements in `set`.

  ## Examples

      iex> Set.size(HashSet.new([1, 2, 3]))
      3

  """
  @spec size(t) :: non_neg_integer
  def size(set) do
