code: def test_multifacet():
      schema = fields.Schema(
          tag=fields.ID(stored=True), size=fields.ID(stored=True)
      )
      with TempIndex(schema, "multifacet") as ix:
          w = ix.writer()
          w.add_document(tag=u("alfa"), size=u("small"))
          w.add_document(tag=u("bravo"), size=u("medium"))
          w.add_document(tag=u("alfa"), size=u("large"))
          w.add_document(tag=u("bravo"), size=u("small"))
          w.add_document(tag=u("alfa"), size=u("medium"))
          w.add_document(tag=u("bravo"), size=u("medium"))
          w.commit()
  
          correct = {
              (u("bravo"), u("medium")): [1, 5],
              (u("alfa"), u("large")): [2],
              (u("alfa"), u("medium")): [4],
              (u("alfa"), u("small")): [0],
              (u("bravo"), u("small")): [3],
          }
  
          with ix.searcher() as s:
              facet = sorting.MultiFacet(["tag", "size"])
              r = s.search(query.Every(), groupedby={"tag/size": facet})
              cats = r.groups(("tag/size"))
              assert cats == correct
  
imports: from __future__ import with_statement
  from datetime import datetime, timedelta
  import random
  from whoosh import fields, query, sorting, columns
  from whoosh.compat import u
  from whoosh.compat import permutations, xrange
  from whoosh.filedb.filestore import RamStorage
  from whoosh.util.testing import TempIndex
label_desc: Use image node_id 26 for calling a global function with example usage: test_multifacet() without return types