code: def clean_db(orion_db):
      """Cleaned the current database prior a test."""
      if isinstance(orion_db, EphemeralDB):
          pass
      elif isinstance(orion_db, MongoDB):
          pass
      elif isinstance(orion_db, PickledDB):
          if os.path.exists(orion_db.host):
              os.remove(orion_db.host)
  
      database = get_db(orion_db)
  
      # Drop experiment data
      database["experiments"].drop()
      database["lying_trials"].drop()
      database["trials"].drop()
      database["workers"].drop()
      database["resources"].drop()
  
      dump_db(orion_db, database)
  
      yield database
  
imports: import os
  from datetime import datetime
  import pytest
  from orion.core.io.database import Database
  from orion.core.io.database.ephemeraldb import EphemeralDB
  from orion.core.io.database.mongodb import MongoDB
  from orion.core.io.database.pickleddb import PickledDB
label_desc: Use image node_id 5 for calling a global function with example usage: clean_db(orion_db) without return types