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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 where(self, key, value):
 """ Filter items by the given key value pair. :param key: The key to filter by :type key: str :param value: The value to filter by :type value: mixed :rtype: Collection """

        return self.filter(lambda item: data_get(item, key) == value)