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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 anlzd_stdev(self, ddof=0, freq=None, **kwargs):
 """Annualized standard deviation with `ddof` degrees of freedom. Parameters ddof : int, default 0 Degrees of freedom, passed to pd.Series.std(). freq : str or None, default None A frequency string used to create an annualization factor. If None, `self.freq` will be used. If that is also None, a frequency will be inferred. If none can be inferred, an exception is raised. It may be any frequency string or anchored offset string recognized by Pandas, such as 'D', '5D', 'Q', 'Q-DEC', or 'BQS-APR'. **kwargs Passed to pd.Series.std(). TODO: freq Returns ------- float """


        if freq is None:
            freq = self._try_get_freq()
            if freq is None:
                raise FrequencyError(msg)
        return nanstd(self, ddof=ddof) * freq ** 0.5