code: def add_slices(self, data, node_or_edge_xml):
      slices_element = node_or_edge_xml.find(
          f"{{{self.NS_GEXF}}}slices"
      )
      if slices_element is not None:
          data["slices"] = []
          for s in slices_element.findall(f"{{{self.NS_GEXF}}}slice"):
              start = s.get("start")
              end = s.get("end")
              data["slices"].append((start, end))
      return data
  
imports: import itertools
  import time
  from xml.etree.ElementTree import Element, ElementTree, SubElement, register_namespace, tostring
  import networkx
  from networkx.utils import open_file
label_desc: Use image node_id 8 for calling the GEXFReader obj's underlying member method code with example usage: obj.add_slices(data, node_or_edge_xml) and returns: data