@type t() :: %Inttegro.Chimes.ChimeEmailMessage{
  from_: Inttegro.Chimes.ChimeEmailMailbox.t() | nil,
  headers: %{optional(String.t()) => String.t()} | nil,
  html: String.t() | nil,
  reply_to: Inttegro.Chimes.ChimeEmailMailbox.t() | nil,
  safety: Inttegro.Chimes.ChimeEmailSafetyResult.t() | nil,
  schema: Inttegro.Chimes.ChimeEmailSchemaMarkup.t() | nil,
  subject: String.t() | nil,
  text: String.t() | nil
}