defmodule MyApp.Accounts  # The Accounts context
  def get_user!(id) → User.t()  # Gets a single user by id
  def list_users() → [User.t()]  # Lists all users, newest first
  def create_user(attrs)  # Creates a user from attrs
  def update_user(user, attrs)
  defp normalize_email(email)
  defmacro __using__(_opts)
