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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 recurse(query, index):
 """ Recursively walk across paths, adding leaves to the index as they're found. """

    for node in app.store.find(query):
        if node.is_leaf:
            index.add(node.path)
        else:
            recurse('{0}.*'.format(node.path), index)