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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 DeregisterHelper(cls, analyzer_helper):
 """Deregisters a format analyzer helper. Args: analyzer_helper (AnalyzerHelper):
 analyzer helper. Raises: KeyError: if analyzer helper object is not set for the corresponding type indicator. """

    if analyzer_helper.type_indicator not in cls._analyzer_helpers:
      raise KeyError(
          'Analyzer helper object not set for type indicator: {0:s}.'.format(
              analyzer_helper.type_indicator))

    analyzer_helper = cls._analyzer_helpers[analyzer_helper.type_indicator]

    cls._FlushCache(analyzer_helper.format_categories)

    del cls._analyzer_helpers[analyzer_helper.type_indicator]