code: def is_legacy_server():
      '''Determine execution mode.
  
      Legacy mode: <= v4.20181215
      '''
      with Session() as session:
          ret = session.Kernel.hello()
      bai_version = ret['version']
      legacy = True if bai_version <= 'v4.20181215' else False
      return legacf is_legacy_server():
      '''Determine execution mode.
  
      Legacy mode: <= v4.20181215
      '''
      with Session() as session:
          ret = session.Kernel.hello()
      bai_version = ret['version']
      legacy = True if bai_version <= 'v4.20181215' else False
      return legacy
docs: Determine execution mode.
  
      Legacy mode: <= v4.20181215