def count(self, start, stop):
        s1 = self.pickler.dumps(start)
        s2 = self.pickler.dumps(stop)
        return self.backend_structure().count(s1, s2)
Count the number of elements bewteen *start* and *stop*.
dataset/ETHPy150Open lsbardel/python-stdnet/stdnet/odm/struct.py/OrderedMixin.count