t() :: %Tai.Events.PositionUpdate{
  account: number(),
  currency: String.t(),
  current_qty: number(),
  current_timestamp: DateTime.t() | String.t(),
  last_price: Decimal.t() | number(),
  liquidation_price: Decimal.t() | number() | nil,
  mark_price: Decimal.t() | number(),
  received_at: DateTime.t(),
  symbol: atom(),
  timestamp: DateTime.t() | String.t(),
  venue_id: atom()
}