code: def run(self):
      build_src = self.get_finalized_command("build_src")
      if build_src.py_modules_dict and self.packages is None:
          self.packages = list(build_src.py_modules_dict.keys())
      old_build_py.run(self)
  
imports: from distutils.command.build_py import build_py
  from numpy.distutils.misc_util import is_string
label_desc: Use image node_id 1 for calling the build_py obj's underlying member method code with example usage: obj.run() without return types