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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def decr(self, name, amount=1):
 """ Decrease the value at key ``name`` by ``amount``. If no key exists, the value will be initialized as 0 - ``amount`` . Like **Redis.DECR** :param string name: the key name :param int amount: decrements :return: the integer value at key ``name`` :rtype: int 7 6 -42 """
                        
        amount = get_positive_integer('amount', amount)
        return self.execute_command('decr', name, amount)