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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 _step_failure(self, exc):
 """ Log failure of a step """

        self.log_crit(u"STEP %d (%s) FAILURE" % (self.step_index, self.step_label))
        self.step_index += 1
        self.log_exc(u"Unexpected error while executing task", exc, True, ExecuteTaskExecutionError)