code: def expand(self):
      self._expand_packages()
      self._canonic_package_data()
      self._canonic_package_data("exclude-package-data")
  
      # A distribution object is required for discovering the correct package_dir
      dist = self._ensure_dist()
      ctx = _EnsurePackagesDiscovered(
          dist, self.project_cfg, self.setuptools_cfg
      )
      with ctx as ensure_discovered:
          package_dir = ensure_discovered.package_dir
          self._expand_data_files()
          self._expand_cmdclass(package_dir)
          self._expand_all_dynamic(dist, package_dir)
  
      dist._referenced_files.update(self._referenced_files)
      return self.config
  
imports: import logging
  import os
  from contextlib import contextmanager
  from functools import partial
  from typing import TYPE_CHECKING, Callable, Dict, Mapping, Optional, Set, Union
  from ..errors import FileError, InvalidConfigError
  from ..warnings import SetuptoolsWarning
  from .None import expand
  from ._apply_pyprojecttoml import _PREVIOUSLY_DEFINED, _MissingDynamic
  from ._apply_pyprojecttoml import apply
label_desc: Use image node_id 5 for calling the _ConfigExpander obj's underlying member method code with example usage: obj.expand() and returns: self