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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 StoreAttribute(self, string='', **unused_kwargs):
 """Store the attribute."""

    logging.debug('Storing attribute {0:s}'.format(repr(string)))

    # TODO: Update the expected number_of_args
    try:
      self.current_expression.SetAttribute(string)
    except AttributeError:
      raise errors.ParseError('Invalid attribute \'{0:s}\''.format(string))

    return 'OPERATOR'