code: def for_step(self, step):
      try:
          is_current_step = bool(step == self._step)
      except Exception as e:
          self._maybe_log_cannot_evaluate(e)
          return None
      else:
          return self._val if is_current_step else None
  
imports: import time
  import warnings
  from guild import python_util
  from guild import util
  from guild.plugin import Plugin
label_desc: Use image node_id 4 for calling the SummaryCache obj's underlying member method code with example usage: obj.for_step(step) and returns: unknown, None