docs: 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)