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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_pandas(self):
 """Convert to pandas Index. Returns ------- pandas.base.Index """

        if not self.is_raw():
            raise ValueError('Cannot convert to pandas Index if not evaluated.')

        from pandas import Index as PandasIndex

        return PandasIndex(self.values,
                           self.dtype,
                           name=self.name)