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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 set_riskfree_rate(self, rf):
 """ Set annual risk-free rate property and calculate properly annualized monthly and daily rates. Then performance stats are recalculated. Affects only this instance of the PerformanceStats. Args: * rf (float):
 Annual `risk-free rate <https://www.investopedia.com/terms/r/risk-freerate.asp>`_ """

        self.rf = rf

        # Note, that we recalculate everything.
        self._update(self.prices)