class_docstr: Test flow to test @parallel.
class_docstr_tok: ["Test","flow","to","test","@","parallel","."]
code: def parallel_step(self):
      self.node_index = current.parallel.node_index
      self.num_nodes = current.parallel.num_nodes
      print("parallel_step: node {} finishing.".format(self.node_index))
      self.next(self.multinode_end)
  
imports: from metaflow import FlowSpec, step, batch, current, parallel, Parameter
label_desc: Use image node_id 2 for calling the ParallelTest obj's underlying member method code with example usage: obj.parallel_step() without return types