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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 _increment_flaky_attribute(cls, test_item, flaky_attribute):
 """ Increments the value of an attribute on a flaky test. :param test_item: The test callable on which to set the attribute :type test_item: `callable` or :class:`nose.case.Test` or :class:`Function` :param flaky_attribute: The name of the attribute to set :type flaky_attribute: `unicode` """

        cls._set_flaky_attribute(test_item, flaky_attribute, cls._get_flaky_attribute(test_item, flaky_attribute) + 1)