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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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]