code: def supported_sub_field_types(driver):
      """Returns supported sub field types
  
      Parameters
      ----------
      driver : str
  
      Returns
      -------
      list
          List with supported field types or None if not specified by driver
  
      """
      field_types_str = _get_metadata_item(
          driver, MetadataItem.CREATION_FIELD_DATA_SUB_TYPES
      )
  
      if field_types_str is None:
          return None
  
      return [
          field_type
          for field_type in field_types_str.split(" ")
          if len(field_type) > 0
      ]
  
file_path: Fiona/fiona/meta.py
imports: import logging
  import xml.etree.ElementTree
  from fiona.env import require_gdal_version
  from fiona.ogrext import _get_metadata_item
label_desc: Use image node_id 10 for calling a global function with example usage: supported_sub_field_types(driver) and returns: unknown, None