@type t() :: %Cyphi.Learner{
  completed: boolean() | nil,
  completed_at: DateTime.t() | nil,
  completed_by_id: integer() | nil,
  course_archived: boolean() | nil,
  course_id: integer() | nil,
  deactivated: boolean() | nil,
  deactivated_at: DateTime.t() | nil,
  deactivated_by_id: integer() | nil,
  enroll_type: String.t() | nil,
  enrolled_at: DateTime.t() | nil,
  enrolled_by_id: integer() | nil,
  grade: String.t() | nil,
  id: integer() | nil,
  last_visited_at: DateTime.t() | nil,
  order_item_id: integer() | nil,
  override_at: DateTime.t() | nil,
  override_by_id: integer() | nil,
  override_comment: String.t() | nil,
  override_percent: number() | nil,
  percent: number() | nil,
  reactivated_at: DateTime.t() | nil,
  reactivated_by_id: integer() | nil,
  started: boolean() | nil,
  started_at: DateTime.t() | nil,
  time_spent: integer() | nil,
  transferred: boolean() | nil,
  transferred_at: DateTime.t() | nil,
  transferred_by_id: integer() | nil,
  transferred_from_id: integer() | nil,
  transferred_to_id: integer() | nil,
  unenrolled: boolean() | nil,
  unenrolled_at: DateTime.t() | nil,
  unenrolled_by_id: integer() | nil,
  user_archived: boolean() | nil,
  user_id: integer()
}