code: def _read_configfile(self):
          
          rc = self.config_filename
          if not os.path.isabs(rc):
              rc = os.path.join(os.path.expanduser('~'), self.config_filename)
          # If there is a setup.cfg in the package, parse it
          files = [f for f in [rc, 'setup.cfg'] if os.path.exists(f)]
          if not files:
              self.config = None
              return
          self.config = ConfigParser()
          self.config.read(files)
          if (not self.is_old_pypi_config() and
                  not self.is_new_pypi_config()):
              # Safety valve
              self.config = None
docs: Read the config file and store it (when valid)