┌considering: -oMt sender_ident = $sender_ident
├──expanding: -oMt sender_ident = $sender_ident
└─────result: -oMt sender_ident = me
┌considering: -oMt sender_ident = $sender_ident
├──expanding: -oMt sender_ident = $sender_ident
└─────result: -oMt sender_ident = me