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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 to_sparse(self, kind='block', fill_value=None):
 """ Convert Series to SparseSeries. Parameters kind : {'block', 'integer'}, default 'block' fill_value : float, defaults to NaN (missing) Value to use for filling NaN values. Returns ------- SparseSeries Sparse representation of the Series. """

        # TODO: deprecate
        from pandas.core.sparse.series import SparseSeries

        values = SparseArray(self, kind=kind, fill_value=fill_value)
        return SparseSeries(
            values, index=self.index, name=self.name
        ).__finalize__(self)