@classmethod
def DeregisterAnalyzer(cls, analyzer_class):
    """Deregisters a analyzer class.

    The analyzer classes are identified based on their lower case name.

    Args:
      analyzer_class (type): class object of the analyzer.

    Raises:
      KeyError: if analyzer class is not set for the corresponding name.
    """
    analyzer_name = analyzer_class.NAME.lower()
    if analyzer_name not in cls._analyzer_classes:
        raise KeyError('analyzer class not set for name: {0:s}'.format(
            analyzer_class.NAME))
    del cls._analyzer_classes[analyzer_name]
