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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 each(self, callback):
 """ Execute a callback over each item. .. code:: collection = Collection([1, 2, 3]) collection.each(lambda x: x + 3) .. warning:: It only applies the callback but does not modify the collection's items. Use the `transform() <#backpack.Collection.transform>`_ method to modify the collection. :param callback: The callback to execute :type callback: callable :rtype: Collection """

        items = self.items

        for item in items:
            if callback(item) is False:
                break

        return self