code: def get_library_for_display_type(display_type):
      
      display_types = get_display_types()
      for key in display_types.keys():
          if display_type in display_types[key]:
              return key
docs: Get library name for ``display_type``, e.g. ``ssd1306`` should return
      ``oled``.
  
      .. versionadded:: 1.2.0
  
      :param display_type: Display type, e.g. ``ssd1306``.
      :type display_type: str
      :rtype: str or None