code: def _add_defaults_c_libs(self):
      if self.distribution.has_c_libraries():
          build_clib = self.get_finalized_command("build_clib")
          self.filelist.extend(build_clib.get_source_files())
  
imports: import os
  import sys
  from glob import glob
  from warnings import warn
  from ..core import Command
  from distutils import dir_util
  from distutils import file_util
  from distutils import archive_util
  from ..text_file import TextFile
  from ..filelist import FileList
  from distutils._log import log
  from ..util import convert_path
  from ..errors import DistutilsOptionError, DistutilsTemplateError
label_desc: Use image node_id 14 for calling the sdist obj's underlying member method code with example usage: obj._add_defaults_c_libs() without return types