<context name="public">
                <extension name="call_in">
                        <condition field="destination_number" expression="test-in">
                                <action application="sleep" data="1000"/>
                                <action application="answer"/>
                                <action application="playback" data="tone_stream://L=5;%(1000,5000,425)"/>
                        </condition>
                </extension>
        </context>