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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_child(self, child_name):
 # pylint: disable=no-self-use """ returns the object with the name supplied """

        child = self.children.get(child_name, None)
        if child:
            return child
        raise ValueError("Value {} not in this tree".format(child_name))