The globally unique identifier of the message.
def get_message_net_id() -> str: ...
message_net_id = property(get_message_net_id, None)
This property contains the globally unique identifier of the message. The class fills the message_net_id with the value of the Message-Id: header. This is a globally unique value normally created by the first mail server the message is sent to.
This property is read-only.