class_docstr: A stage in a linear workflow.
class_docstr_tok: ["A","stage","in","a","linear","workflow","."]
code: def work_units(
      self, previous_phase: Optional["Phase"]
  ) -> Iterator[WorkUnit]:
      pass
  
imports: import abc
  from typing import Iterable, Iterator, Optional
  from adanet.experimental.storages.in_memory_storage import InMemoryStorage
  from adanet.experimental.storages.storage import Storage
  from adanet.experimental.work_units.work_unit import WorkUnit
  import tensorflow.compat.v2
label_desc: Use image node_id 2 for calling the Phase obj's underlying member method code with example usage: obj.work_units(previous_phase) without return types