code: def exists(key, host=None, port=None, db=None, password=None):
      '''
      Return true if the key exists in redis
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' redis.exists foo
      '''
      server = _connect(host, port, db, password)
      return server.exists(keyf exists(key, host=None, port=None, db=None, password=None):
      '''
      Return true if the key exists in redis
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' redis.exists foo
      '''
      server = _connect(host, port, db, password)
      return server.exists(key)
docs: Return true if the key exists in redis
  
      CLI Example:
  
      .. code-block:: bash
  
          salt '*' redis.exists foo