Custom Story Error

[Hungerzz]

Hello guys,can you show me how to fix this problem? Here is the script
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19 void AddEntityCollideCallback("PlayerStop", "", "SetPlayerActive", "", 1);
20
21 void SetPlayerActive(false);
22 {
23 StartPlayerLookAt("Grunt", 5.0f, 5.0f, "AddTimer");
24 AddTimer("", 5.0f, "StartWalk");
25 }
26 void StartWalk(string &in asTimer)
27 {
28 SetPlayerActive(true);
29 StopPlayerLookAt();
30 }
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And then this error shows up when i start the map :

main(22,1) ERR: Unexpected token '{'

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I'm trying to make player stop and look at monster for 5 seconds,and then walk again after 5 seconds.