# defmodule MyApp.Address do
#   use Ecto.Schema
#   import Ecto.Changeset

#   schema "addresses" do
#     field :city, :string
#     field :street, :string
#     field :number, :integer
#     belongs_to(:user, MyApp.User)
#   end

#   def changeset(user, params \\ %{}) do
#     user
#     |> cast(params, [:city, :street, :number])
#     |> validate_required([:city, :number])
#   end
# end

# defmodule Address do
#   use Parameter.Schema
#   import Ecto.Changeset
#   import Parameter.Extensions.Changeset

#   param do
#     field :city, :string
#     field :street, :string
#     field :number, :integer
#   end

#   def changeset(params) do
#     Address
#     |> cast(params)
#     |> validate_required(:city)
#     |> validate_required(:number)
#   end
# end