Asterisk feature code

nano  /etc/asterisk/features.conf

  testfeature => #9,peer,Playback,tt-monkeys  ;Allow both the caller and callee to play
; ;tt-monkeys to the opposite channel

 /etc/asterisk/extensions.conf

[test_feauture_code]
exten =>_412,1,Set(__DYNAMIC_FEATURES=testfeature)
exten=>_412,2,Dial(SIP/102,,Tt)

Now you just can dial  411 and then #9