MLLP.PacketFramer.handle_packet

You're seeing just the callback handle_packet, go back to MLLP.PacketFramer module for more information.
Link to this callback

handle_packet(packet, state)

Specs

handle_packet(packet :: String.t(), state :: MLLP.FramingContext.t()) ::
  {:ok, MLLP.FramingContext.t()}