code: def GetAnalyzerInstance(cls, analyzer_name):
      
      analyzer_name = analyzer_name.lower()
      if analyzer_name not in cls._analyzer_classes:
        raise KeyError(
            'analyzer class not set for name: {0:s}.'.format(analyzer_name))
  
      analyzer_class = cls._analyzer_classes[analyzer_name]
      return analyzer_class()
docs: Retrieves an instance of a specific analyzer.
  
      Args:
        analyzer_name (str): name of the analyzer to retrieve.
  
      Returns:
        BaseAnalyzer: analyzer instance.
  
      Raises:
        KeyError: if analyzer class is not set for the corresponding name.