code: def _upsample(self, method, limit=None, fill_value=None):
          
  
          # we may need to actually resample as if we are timestamps
          if self.kind == 'timestamp':
              return super()._upsample(method, limit=limit,
                                       fill_value=fill_value)
  
          self._set_binner()
          ax = self.ax
          obj = self.obj
          new_index = self.binner
  
          # Start vs. end of period
          memb = ax.asfreq(self.freq, how=self.convention)
  
          # Get the fill indexer
          indexer = memb.get_indexer(new_index, method=method, limit=limit)
          return self._wrap_result(_take_new_index(
              obj, indexer, new_index, axis=self.axis))
docs: Parameters
          ----------
          method : string {'backfill', 'bfill', 'pad', 'ffill'}
              method for upsampling
          limit : int, default None
              Maximum size gap to fill when reindexing
          fill_value : scalar, default None
              Value to use for missing values
  
          See Also
          --------
          .fillna