Warning: Function state mutability can be restricted to pure
 --> model_checker_ext_calls_trusted_chc/input.sol:5:2:
  |
5 | 	function f() public view returns (uint) {
  | 	^ (Relevant source part starts here and spans across multiple lines).

Info: CHC: 1 verification condition(s) proved safe! Enable the model checker option "show proved safe" to see all of them.