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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 of_cls(self):
 """ DONT USE. Will be deleted soon. Use ``self.of``! """

        if isinstance(self.of, six.string_types):
            warnings.warn('When using Range programatically, dont pass "of" param as string!')
            return Register.get_task_cls(self.of)
        return self.of