You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: has_groups.rb
    path of file: ./repos/zammad/app/models/concerns
    
    the code of the file until where you have to start completion: # Copyright (C) 2012-2024 Zammad
    
  def flush_group_access_buffer
    # group_access_buffer is at least an empty Array
    # if changes to the map were performed
    # otherwise it's just an update of other attributes
    return if group_access_buffer.nil?

    yield
    self.group_access_buffer = nil
  end