class_docstr: A format that stores positions and per-position boost information
  in each posting.
  
  Supports: frequency, weight, positions, position_boosts.
class_docstr_tok: ["A","format","that","stores","positions","and","per-position","boost","information","in","each","posting",".","Supports",":","frequency",",","weight",",","positions",",","position_boosts","."]
code: def word_values(self, value, analyzer, **kwargs):
      fb = self.field_boost
      seen = defaultdict(list)
  
      kwargs["positions"] = True
      kwargs["boosts"] = True
      for t in tokens(value, analyzer, kwargs):
          pos = t.pos
          boost = t.boost
          seen[t.text].append((pos, boost))
  
      for w, poses in iteritems(seen):
          value = self.encode(poses)
          yield (w, len(poses), sum(p[1] for p in poses) * fb, value)
  
imports: from collections import defaultdict
  from whoosh.analysis import unstopped, entoken
  from whoosh.compat import iteritems, dumps, loads, b
  from whoosh.system import emptybytes
  from whoosh.system import _INT_SIZE, _FLOAT_SIZE
  from whoosh.system import pack_uint, unpack_uint, pack_float, unpack_float
label_desc: Use image node_id 1 for calling the PositionBoosts obj's underlying member method code with example usage: obj.word_values(value, analyzer) without return types