Hur bifoga ett attachment till Mail?

Prova något åt det här hållet.

set bifogadfil to choose file
tell application "Mail"
	set brevet to make new outgoing message with properties {visible:true, subject:"Här kommer filen", content:"Varsågod."}
	tell content of brevet
		make new attachment with properties {file name:bifogadfil} at after last paragraph
	end tell
end tell