code: def load_act_node(self) -> ActNode:
          
          act_nodes = ActNode.build_body(self.node.body)
  
          if not act_nodes:
              raise ValidationError(self.first_line_no, self.node.col_offset, 'AAA01 no Act block found in test')
  
          # Allow `pytest.raises` and `self.assertRaises()` in assert nodes - if
          # any of the additional nodes are `pytest.raises`, then raise
          for a_n in act_nodes[1:]:
              if a_n.block_type in [ActNodeType.marked_act, ActNodeType.result_assignment]:
                  raise ValidationError(
                      self.first_line_no,
                      self.node.col_offset,
                      'AAA02 multiple Act blocks found in test',
                  )
  
          return act_nodes[0]
docs: Raises:
              ValidationError: AAA01 when no act block is found and AAA02 when
                  multiple act blocks are found.