docs: def _getConfigFile(self, config):
          """
          Retrieves a file descriptor to a configuration file to process.
  
          Inputs: config - The _Config object which is being populated.
  
          Outputs: An open file descriptor to the configuration file to parse in read mode if successful, else None.
          """
  
          joinPath = lambda p: (os.path.join(p) if isinstance(p, (tuple, list)) else p)
  
          if self.filepathConfig is not None and self.filenameConfig is not None:
              if hasattr(config, self.filepathConfig) and hasattr(config, self.filenameConfig):
                  path = joinPath(getattr(config, self.filepathConfig))
                  name = getattr(config, self.filenameConfig)
  
                  if os.path.isfile(os.path.join(path, name)):
                      return open(os.path.join(path, name), 'r')
  
          if self.filepath is not None and self.filename is not None:
              path = joinPath(self.filepath)
              name = self.filename
  
              if os.path.isfile(os.path.join(path, name)):
                  return open(os.path.join(path, name), 'r')