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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_all_gateways(bpmn_graph):
 """ Returns a list with all gateways in diagram :param bpmn_graph: an instance of BpmnDiagramGraph representing BPMN model. :return: a list with all gateways in diagram """

    gateways = filter(lambda node: node[1]['type'] in GATEWAY_TYPES, bpmn_graph.get_nodes())

    return gateways