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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 _reset_kind_map(cls):
 """Clear the kind map. Useful for testing."""

    # Preserve "system" kinds, like __namespace__
    keep = {}
    for name, value in cls._kind_map.iteritems():
      if name.startswith('__') and name.endswith('__'):
        keep[name] = value
    cls._kind_map.clear()
    cls._kind_map.update(keep)