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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_unconnected_nodes(sentence_graph):
 """ Takes a TigerSentenceGraph and returns a list of node IDs of unconnected nodes. A node is unconnected, if it doesn't have any in- or outgoing edges. A node is NOT considered unconnected, if the graph only consists of that particular node. Parameters sentence_graph : TigerSentenceGraph a directed graph representing one syntax annotated sentence from a TigerXML file Returns ------- unconnected_node_ids : list of str a list of node IDs of unconnected nodes """

    return [node for node in sentence_graph.nodes_iter()
            if sentence_graph.degree(node) == 0 and
            sentence_graph.number_of_nodes() > 1]