code: def generate_field_types():
      """
      Produce a unique set of field types in a consistent order.
  
      This ensures that tests are able to run in parallel.
      """
      types = set(FIELD_TYPES)
      types.remove(None)
      return list(sorted(types)) + [None]
  
imports: import os
  import tempfile
  import pytest
  import fiona
  from fiona.drvsupport import driver_mode_mingdal
  from fiona.env import GDALVersion
  from fiona.errors import SchemaError, UnsupportedGeometryTypeError, DriverSupportError
  from fiona.model import Feature
  from fiona.schema import FIELD_TYPES, normalize_field_type
  from .conftest import get_temp_filename
  from .conftest import requires_only_gdal1, requires_gdal2
label_desc: Use image node_id 10 for calling a global function with example usage: generate_field_types() and returns: unknown