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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 decrement(self, key, cache=None, amount=1):
 """A convenience function for passing negative values to increment. Keyword arguments: key -- the key the item is stored under. Required. cache -- the cache the item belongs to. Defaults to None, which uses self.name. If no name is set, raises a ValueError. amount -- the amount to decrement the value by. Can be negative to increment the value. Defaults to 1. """

        amount = amount * -1

        return self.increment(key=key, cache=cache, amount=amount)