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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 get_by_id(self, id):
 """ Return object based on ``child_id_attribute``. Parameters val : str Returns ------- object Notes ----- Based on `.get()`_ from `backbone.js`_. .. _backbone.js: http://backbonejs.org/ .. _.get():
 http://backbonejs.org/#Collection-get """

        for child in self.children:
            if child[self.child_id_attribute] == id:
                return child
            else:
                continue

        return None