code: def _setup_custom_reader_config(base_dir):
      reader_config = base_dir.mkdir("readers").join("fake.yaml")
      with open(reader_config, "wt") as comp_file:
          # abstract base classes can't be converted so we do raw string
          comp_file.write(
              """
  reader:
    name: "fake"
    reader: !!python/name:satpy.readers.yaml_reader.FileYAMLReader
    data_files:
      - url: {}
        known_hash: null
      - url: {}
        filename: "README2.rst"
        known_hash: null
  file_types: {{}}
  """.format(
                  README_URL, README_URL
              )
          )
  
imports: from unittest import mock
  import pytest
  import yaml
  from satpy.aux_download import DataDownloadMixin
  from satpy.modifiers import ModifierBase
label_desc: Use image node_id 2 for calling a global function with example usage: _setup_custom_reader_config(base_dir) without return types