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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 is_causal_sink(graph: BELGraph, node: BaseEntity) -> bool: """Return true if the node is a causal sink. - Does have causal in edge(s) - Doesn't have any causal out edge(s) """

    return has_causal_in_edges(graph, node) and not has_causal_out_edges(graph, node)