code: def rank(self, dte):
          '''The rank of a given *dte* in the timeseries'''
          timestamp = self.pickler.dumps(dte)
          return self.backend_structure().rank(timestampf rank(self, dte):
          '''The rank of a given *dte* in the timeseries'''
          timestamp = self.pickler.dumps(dte)
          return self.backend_structure().rank(timestamp)
docs: The rank of a given *dte* in the timeseries