Decrease the value of ``key`` in zset ``name`` by ``amount``. If no key
        exists, the value will be initialized as 0 - ``amount`` 

        :param string name: the zset name
        :param string key: the key name        
        :param int amount: increments
        :return: the integer value of ``key`` in zset ``name``
        :rtype: int

        >>> ssdb.zdecr('zset_2', 'key1', 7)
        36
        >>> ssdb.zdecr('zset_2', 'key2', 3)
        311
        >>> ssdb.zdecr('zset_2', 'key_not_exists', 101)
        -101
        >>> ssdb.zdecr('zset_not_exists', 'key_not_exists', 8848)
        -8848

def zdecr(self, name, key, amount=1):
        """
        Decrease the value of ``key`` in zset ``name`` by ``amount``. If no key
        exists, the value will be initialized as 0 - ``amount`` 

        :param string name: the zset name
        :param string key: the key name        
        :param int amount: increments
        :return: the integer value of ``key`` in zset ``name``
        :rtype: int

        >>> ssdb.zdecr('zset_2', 'key1', 7)
        36
        >>> ssdb.zdecr('zset_2', 'key2', 3)
        311
        >>> ssdb.zdecr('zset_2', 'key_not_exists', 101)
        -101
        >>> ssdb.zdecr('zset_not_exists', 'key_not_exists', 8848)
        -8848
        """                                        
        amount = get_positive_integer('amount', amount)
        return self.execute_command('zdecr', name, key, amount)