Exgencode.Pdu.Protocol.set_offsets

You're seeing just the function set_offsets, go back to Exgencode.Pdu.Protocol module for more information.
Link to this function

set_offsets(pdu, version)

Specs

set_offsets(Exgencode.pdu(), nil | Version.version()) :: Exgencode.pdu()

Calculate the values of all offset fields.