old_contents: # -*- coding: utf-8 -*-
   """Memcached and in-memory cache result backend."""
   from __future__ import absolute_import
   
   from kombu.utils import cached_property
   from kombu.utils.url import _parse_url
   
   import boto3
   import logging
   import decimal
   from time import sleep
   
   from .base import KeyValueStoreBackend
   
   __all__ = ['DynamoDBBackend']
   
   
   class Client(object):
       """docstring for Client"""
   
       def __init__(self, url):
           super(Client, self).__init__()
           _, region_name, _, access_key, secret_key, table_name, _ = _parse_url(url)
           session = boto3.Session(
               aws_access_key_id=access_key,
               aws_secret_access_key=secret_key
           )
           dynamodb = session.resource('dynamodb', region_name=region_name)
           table = dynamodb.Table(table_name)
           self.table = table
           self.dynamodb = dynamodb
   
       def get(self, key):
           while True:
               response = self.table.get_item(
                   Key={
                       'id': key
                   },
                   ConsistentRead=True
               )
               item = response.get('Item')
               if item:
                   break
               else:
                   sleep(0.1)
           return item['result']
  
new_contents: # -*- coding: utf-8 -*-
   """Memcached and in-memory cache result backend."""
   from __future__ import absolute_import
   
   from kombu.utils import cached_property
   from kombu.utils.url import _parse_url
   
   import boto3
   import logging
   import decimal
   from time import sleep
   
   from .base import KeyValueStoreBackend
   
   __all__ = ['DynamoDBBackend']
   
   
   class Client(object):
       """docstring for Client"""
   
       def __init__(self, url):
           super(Client, self).__init__()
           _, region_name, _, access_key, secret_key, table_name, _ = _parse_url(url)
           session = boto3.Session(
               aws_access_key_id=access_key,
               aws_secret_access_key=secret_key
           )
           dynamodb = session.resource('dynamodb', region_name=region_name)
           table = dynamodb.Table(table_name)
           self.table = table
           self.dynamodb = dynamodb
   
       def get(self, key):
           while True:
               response = self.table.get_item(
                   Key={
                       'id': key
                   },
                   ConsistentRead=True
               )
               item = response.get('Item')
               if item:
                   break
               else:
                   sleep(0.1)
           return item['result']
  
  class DynamoDBBackend(KeyValueStoreBackend):
   
       supports_native_join = True
       implements_incr = True
       supports_autoexpire = False
   
       def __init__(self, url=None, *args, **kwargs):
           super(DynamoDBBackend, self).__init__(*args, **kwargs)
           self.url = url
   
       def get(self, key):
           return self.client.get(key)
  
subject: add in the key value backend class