docs: def concretize_load_idx(self, idx, strategies=None):
          """
          Concretizes a load index.
  
          :param idx:             An expression for the index.
          :param strategies:      A list of concretization strategies (to override the default).
          :param min_idx:         Minimum value for a concretized index (inclusive).
          :param max_idx:         Maximum value for a concretized index (exclusive).
          :returns:               A list of concrete indexes.
          """
          if isinstance(idx, int):
              return [idx]
          elif not self.state.solver.symbolic(idx):
              return [self.state.solver.eval(idx)]
  
          strategies = self.load_strategies if strategies is None else strategies
          return self._apply_concretization_strategies(idx, strategies, 'load')