def foreach_blank():
    for node in NodeIterator():
        if (node.last and (node.type == node.last.type == NodeType.BLANK)):
            merge_prev_node(node)
def foreach_blank():
    for node in NodeIterator():
        if (node.last and (node.type == node.last.type == NodeType.BLANK)):
            merge_prev_node(node)