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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 GetOutputClass(cls, name):
 """Retrieves the output class for a specific name. Args: name (str):
 name of the output module. Returns: type: output module class. Raises: KeyError: if there is no output class found with the supplied name. ValueError: if name is not a string. """

    if not isinstance(name, py2to3.STRING_TYPES):
      raise ValueError('Name attribute is not a string.')

    name = name.lower()
    if name not in cls._output_classes:
      raise KeyError(
          'Name: [{0:s}] not registered as an output module.'.format(name))

    return cls._output_classes[name]