def _vsids_lit_unset(self, lit):
        var = abs(lit)
        heappush(self.lit_heap, (self.lit_scores[var], var))
        heappush(self.lit_heap, (self.lit_scores[-var], -var))
Handle the unsetting of a literal for the VSIDS heuristic.
dataset/ETHPy150Open sympy/sympy/sympy/logic/algorithms/dpll2.py/SATSolver._vsids_lit_unset