code: def refresh(self, runs):
      for run in runs:
          for path, cur_digest, reader in tfevent.scalar_readers(
              run.dir
          ):
              self._maybe_refresh_run_scalars(
                  run, path, cur_digest, reader
              )
  
imports: import logging
  import os
  import sqlite3
  from guild import run_util
  from guild import tfevent
  from guild import util
  from guild import var
label_desc: Use image node_id 2 for calling the ScalarReader obj's underlying member method code with example usage: obj.refresh(runs) without return types