Redis driver: DeprecationWarning

I get

2023-10-02 07:01:04,523 43 WARNING py.warnings: /usr/local/lib/python3.9/dist-packages/flanker/addresslib/drivers/redis_driver.py:6: DeprecationWarning: Using or importing the ABCs from 'collections' instead of from 'collections.abc' is deprecated since Python 3.3, and in 3.10 it will stop working
  File "/usr/lib/python3.9/threading.py", line 912, in _bootstrap
    self._bootstrap_inner()
  File "/usr/lib/python3.9/threading.py", line 954, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.9/threading.py", line 892, in run
    self._target(*self._args, **self._kwargs)
  File "/opt/odoo/bin/odoo/service/server.py", line 1112, in _runloop
    self.process_work()
  File "/opt/odoo/bin/odoo/service/server.py", line 1203, in process_work
    base.models.ir_cron.ir_cron._process_jobs(db_name)
  File "/opt/odoo/bin/odoo/addons/base/models/ir_cron.py", line 116, in _process_jobs
    registry[cls._name]._process_job(db, cron_cr, job)
  File "/opt/odoo/bin/odoo/addons/base/models/ir_cron.py", line 325, in _process_job
    ir_cron._callback(job['cron_name'], job['ir_actions_server_id'], job['id'])
  File "/opt/odoo/bin/odoo/addons/base/models/ir_cron.py", line 368, in _callback
    self.env['ir.actions.server'].browse(server_action_id).run()
  File "/opt/odoo/bin/odoo/addons/base/models/ir_actions.py", line 668, in run
    res = runner(run_self, eval_context=eval_context)
  File "/opt/odoo/bin/addons/website/models/ir_actions_server.py", line 61, in _run_action_code_multi
    res = super(ServerAction, self)._run_action_code_multi(eval_context)
  File "/opt/odoo/bin/odoo/addons/base/models/ir_actions.py", line 538, in _run_action_code_multi
    safe_eval(self.code.strip(), eval_context, mode="exec", nocopy=True, filename=str(self))  # nocopy allows to return 'action'
  File "/opt/odoo/bin/odoo/tools/safe_eval.py", line 362, in safe_eval
    return unsafe_eval(c, globals_dict, locals_dict)
  File "ir.actions.server(123,)", line 1, in <module>
  File "/opt/odoo/bin/addons/mail/models/fetchmail.py", line 185, in _fetch_mails
    return self.search([('state', '=', 'done'), ('server_type', '!=', 'local')]).fetch_mail()
  File "/opt/odoo/bin/addons/mail/models/fetchmail.py", line 215, in fetch_mail
    self._cr.commit()
  File "/opt/odoo/bin/odoo/sql_db.py", line 454, in commit
    self.flush()
  File "/opt/odoo/bin/odoo/sql_db.py", line 127, in flush
    self.transaction.flush()
  File "/opt/odoo/bin/odoo/api.py", line 870, in flush
    env_to_flush.flush_all()
  File "/opt/odoo/bin/odoo/api.py", line 732, in flush_all
    self._recompute_all()
  File "/opt/odoo/bin/odoo/api.py", line 728, in _recompute_all
    self[field.model_name]._recompute_field(field)
  File "/opt/odoo/bin/odoo/models.py", line 6170, in _recompute_field
    field.recompute(records)
  File "/opt/odoo/bin/odoo/fields.py", line 1365, in recompute
    apply_except_missing(self.compute_value, recs)
  File "/opt/odoo/bin/odoo/fields.py", line 1338, in apply_except_missing
    func(records)
  File "/opt/odoo/bin/odoo/fields.py", line 1387, in compute_value
    records._compute_field_value(self)
  File "/opt/odoo/bin/addons/mail/models/mail_thread.py", line 403, in _compute_field_value
    return super()._compute_field_value(field)
  File "/opt/odoo/bin/odoo/models.py", line 4203, in _compute_field_value
    fields.determine(field.compute, self)
  File "/opt/odoo/bin/odoo/fields.py", line 97, in determine
    return needle(*args)
  File "/opt/odoo/bin/addons/crm/models/crm_lead.py", line 491, in _compute_probabilities
    lead_probabilities = self._pls_get_naive_bayes_probabilities()
  File "/opt/odoo/bin/addons/crm/models/crm_lead.py", line 2059, in _pls_get_naive_bayes_probabilities
    leads_values_dict = self._pls_get_lead_pls_values(domain=domain)
  File "/opt/odoo/bin/addons/crm/models/crm_lead.py", line 2606, in _pls_get_lead_pls_values
    value = lead[field].id if isinstance(lead[field], models.BaseModel) else lead[field]
  File "/opt/odoo/bin/odoo/models.py", line 5868, in __getitem__
    return self._fields[key].__get__(self, type(self))
  File "/opt/odoo/bin/odoo/fields.py", line 1157, in __get__
    self.recompute(record)
  File "/opt/odoo/bin/odoo/fields.py", line 1365, in recompute
    apply_except_missing(self.compute_value, recs)
  File "/opt/odoo/bin/odoo/fields.py", line 1338, in apply_except_missing
    func(records)
  File "/opt/odoo/bin/odoo/fields.py", line 1387, in compute_value
    records._compute_field_value(self)
  File "/opt/odoo/bin/addons/mail/models/mail_thread.py", line 403, in _compute_field_value
    return super()._compute_field_value(field)
  File "/opt/odoo/bin/odoo/models.py", line 4203, in _compute_field_value
    fields.determine(field.compute, self)
  File "/opt/odoo/bin/odoo/fields.py", line 97, in determine
    return needle(*args)
  File "/opt/odoo/bin/addons/crm/models/crm_lead.py", line 477, in _compute_email_state
    if mail_validation.mail_validate(email):
  File "/opt/odoo/bin/addons/mail/tools/mail_validation.py", line 17, in mail_validate
    return bool(address.validate_address(email))
  File "/usr/local/lib/python3.9/dist-packages/flanker/utils.py", line 64, in wrapper
    return_value = f(*args, **kwargs)
  File "/usr/local/lib/python3.9/dist-packages/flanker/addresslib/address.py", line 312, in validate_address
    exchanger, mx_metrics = mail_exchanger_lookup(paddr.hostname, metrics=True)
  File "/usr/local/lib/python3.9/dist-packages/flanker/utils.py", line 64, in wrapper
    return_value = f(*args, **kwargs)
  File "/usr/local/lib/python3.9/dist-packages/flanker/addresslib/validate.py", line 146, in mail_exchanger_lookup
    in_cache, cache_value = lookup_exchanger_in_cache(domain)
  File "/usr/local/lib/python3.9/dist-packages/flanker/addresslib/validate.py", line 188, in lookup_exchanger_in_cache
    lookup = _get_mx_cache()[domain]
  File "/usr/local/lib/python3.9/dist-packages/flanker/addresslib/validate.py", line 238, in _get_mx_cache
    from flanker.addresslib.drivers.redis_driver import RedisCache
  File "/usr/local/lib/python3.9/dist-packages/flanker/addresslib/drivers/redis_driver.py", line 6, in <module>
    class RedisCache(collections.MutableMapping):

Start with flanker/addresslib/drivers/redis_driver.py, especially line 6 identified in the warning. Check the Redis driver import under Python 3.9 and newer, then verify that loading RedisCache no longer emits the reported DeprecationWarning.