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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 remember(self, key, minutes, callback):
 """ Get an item from the cache, or store the default value. :param key: The cache key :type key: str :param minutes: The lifetime in minutes of the cached value :type minutes: int or datetime :param callback: The default function :type callback: mixed :rtype: mixed """

        # If the item exists in the cache we will just return this immediately
        # otherwise we will execute the given callback and cache the result
        # of that execution for the given number of minutes in storage.
        val = self.get(key)
        if val is not None:
            return val

        val = value(callback)

        self.put(key, val, minutes)

        return val