bel(system,know(user,effect($B9T$/(B(user,$B6d9T(B),$B$$$k(B(user,$B6d9T(B)))).
bel(system,know(user,effect($B?=@A(B(user,$BH/9T(B($BJ6<:>ZL@=q(B)),$B;}$D(B(user,$BJ6<:>ZL@=q(B)))).
bel(system,know(user,effect($B9T$/(B(user,$B7Y;!=p(B),$B$$$k(B(user,$B7Y;!=p(B)))).
bel_ref(system,aaa,at_loc,user,[]).
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