code: def peek_step(self, val: ArrayValue,
                    sn: "DataNode") -> Tuple[Optional[Value], "DataNode"]:
          
          try:
              return val[self.index], sn
          except (IndexError, KeyError, TypeError):
              return None, sn
docs: Return entry value addressed by the receiver + its schema node.
  
          Args:
              val: Current value (array).
              sn:  Current schema node.