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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 extend_children(self, parent, wanted_children, child_class, child_glossary=None):
 """ Extend the number of children so that the parent object contains wanted children. No child will be removed if wanted_children is smaller than the current number of children. """

        from cms.api import add_plugin
        current_children = parent.get_num_children()
        for _ in range(current_children, wanted_children):
            child = add_plugin(parent.placeholder, child_class, parent.language, target=parent)
            if isinstance(child_glossary, dict):
                child.glossary.update(child_glossary)
            child.save()