How do I get live match player stats?

[HarlockOfficial]

As part of a class, I have the following code:

cass.set_riot_api_key(RiotEnv.API_KEY)
self.account = cass.get_account(name=account_name, tagline=account_tagline, region=region.value)
self.summoner = self.account.summoner
self.match = self.summoner.current_match
participants = self.match.participants
self.player = [p for p in participants if p.summoner == self.summoner][0]
self.stats = cass.core.match.ParticipantStats(match=self.match, participant=self.player)

Reading the library code and the online documentation, I understood that it is possible to use the instance of ParticipantStats to obtain the live values for the kda, champion level, etc.

The first time I call self.stats.kills I get the following error:

Traceback (most recent call last):
  File "[redacted_1]\cassiopeia\core\match.py", line 56, in wrapper
    return method(self, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "[redacted_1]\cassiopeia\core\match.py", line 1217, in kills
    return self._data[ParticipantStatsData].kills
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'ParticipantStatsData' object has no attribute 'kills'

During handling of the above exception, another exception occurred:

...

File "[redacted_2]", line 22, in [redacted_3]
  reward = self.stats.kills * 100
           ^^^^^^^^^^^^^^^^
File "[redacted_1]\cassiopeia\core\match.py", line 59, in wrapper
  match = getattr(self, "_{}__match".format(self.__class__.__name__))
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'ParticipantStats' object has no attribute '_ParticipantStats__match'

I think I am missing some data in the ParicipantStats constructor or that I should obtain that value using other objects as I did for the match participants.
Following the documentation I can't find a path from the account to the live game participant stats.