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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 valid(self, inplace=False, **kwargs):
 """ Return Series without null values. .. deprecated:: 0.23.0 Use :meth:`Series.dropna` instead. """

        warnings.warn("Method .valid will be removed in a future version. "
                      "Use .dropna instead.", FutureWarning, stacklevel=2)
        return self.dropna(inplace=inplace, **kwargs)