code: def _value_ref(self, column, value, *, dumped=False, inner=False):
          
          ref = ":v{}".format(self.next_index)
  
          # Need to dump this value
          if not dumped:
              typedef = column.typedef
              for segment in path_of(column):
                  typedef = typedef[segment]
              if inner:
                  typedef = typedef.inner_typedef
              value = self.engine._dump(typedef, value)
  
          self.attr_values[ref] = value
          self.counts[ref] += 1
          return ref, value
docs: inner=True uses column.typedef.inner_type instead of column.typedef