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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 _shift_factor(self, factor, shift):
 """ Shifting the factor to a certain required time slice. Parameters: factor: DiscreteFactor The factor which needs to be shifted. shift: int The new timeslice to which the factor should belong to. """

        new_scope = self._shift_nodes(factor.scope(), shift)
        return DiscreteFactor(new_scope, factor.cardinality, factor.values)