old_contents: import steem as stm
  
  _shared_steem_instance = None
  
  
  def shared_steem_instance():
      global _shared_steem_instance
      if not _shared_steem_instance:
          _shared_steem_instance = stm.Steem()  # todo: add piston config
      return _shared_steem_instance
  
new_contents: import steem as stm
  
  _shared_steem_instance = None
  
  
  def shared_steem_instance():
      """ This method will initialize _shared_steem_instance and return it.
      The purpose of this method is to have offer single default Steem instance that can be reused by multiple classes.
      """
      global _shared_steem_instance
      if not _shared_steem_instance:
          _shared_steem_instance = stm.Steem()  # todo: add piston config
      return _shared_steem_instance
  
  
  def set_shared_steem_instance(steem_instance):
      """ This method allows us to override default steem instance for all users of
      _shared_steem_instance.
      """
      global _shared_steem_instance
      _shared_steem_instance = steem_instance
  
subject: enable global steem instance overloading