@staticmethod<EOL><INDENT>def import_data_object_to_graph(diagram_graph, process_id, process_attributes, data_object_element):<DEDENT>
BpmnDiagramGraphImport.import_flow_node_to_graph(diagram_graph, process_id, process_attributes,<EOL>data_object_element)<EOL>data_object_id = data_object_element.getAttribute(consts.Consts.id)<EOL>diagram_graph.node[data_object_id][consts.Consts.is_collection] =data_object_element.getAttribute(consts.Consts.is_collection)if data_object_element.hasAttribute(consts.Consts.is_collection) else "<STR_LIT:false>"<EOL>
Adds to graph the new element that represents BPMN data object.
Data object inherits attributes from FlowNode. In addition, an attribute 'isCollection' is added to the node.

:param diagram_graph: NetworkX graph representing a BPMN process diagram,
:param process_id: string object, representing an ID of process element,
:param process_attributes: dictionary that holds attribute values of 'process' element, which is parent of
    imported flow node,
:param data_object_element: object representing a BPMN XML 'dataObject' element.