Problem with dialplan

Hello, guys! I am a newbie in Asterisk. I have a problem with writing a context for autodialing... Well, this is my extensions_custom.conf: [my-test-context] extern => s,1,Answer()
extern => s,n,Wait(1)
extern => s,n,Playback(hello-world)
extern => s,n,Hangup()

My call file:

Channel: IAX2/1
Callerid: 0
Context: my-test-context
Extension: s

My log error:

[2014-03-05 19:43:11] WARNING[3016] pbx_config.c: ==!!== Unknown directive: extern at line 2 of /etc/asterisk/extensions_custom.conf -- IGNORING!!!
[2014-03-05 19:43:11] WARNING[3016] pbx_config.c: ==!!== Unknown directive: extern at line 3 of /etc/asterisk/extensions_custom.conf -- IGNORING!!!
[2014-03-05 19:43:11] WARNING[3016] pbx_config.c: ==!!== Unknown directive: extern at line 4 of /etc/asterisk/extensions_custom.conf -- IGNORING!!!
[2014-03-05 19:43:11] WARNING[3016] pbx_config.c: ==!!== Unknown directive: extern at line 5 of /etc/asterisk/extensions_custom.conf -- IGNORING!!!

You need to go back to your tutorials, you haven’t quite got it yet. this will fix the first problem

sed -i ‘s/extern => s/exten => s/’ /etc/asterisk/extensions_custom.conf

huh, sorry )) thanks guy