##### SUMMARY
strategy contains call to Display.deprecated or AnsibleModule.deprecate and is scheduled for removal

```
lib/ansible/plugins/strategy/__init__.py:937:16: ansible-deprecated-version: Deprecated version ('2.12') found in call to Display.deprecated or AnsibleModule.deprecate (0%)
```

##### ISSUE TYPE
 - Bug Report

##### COMPONENT NAME
```
lib/ansible/plugins/strategy/__init__.py
```

##### ANSIBLE VERSION
```
2.12
```

##### CONFIGURATION
N/A

##### OS / ENVIRONMENT
N/A

##### STEPS TO REPRODUCE
N/A

##### EXPECTED RESULTS
N/A

##### ACTUAL RESULTS
N/A

self._flushed_hosts = dict()
        self._results = deque()
        self._handler_results = deque()
        self._results_lock = threading.Condition(threading.Lock())
        
        self._results_thread = threading.Thread(target=results_thread_main, args=(self,))
        self._results_thread.daemon = True
        self._results_thread.start()
        
        
        self._active_connections = dict()
        
        
        
        self._hosts_cache = []
        self._hosts_cache_all = []
        self.debugger_active = C.ENABLE_TASK_DEBUGGER
    def _set_hosts_cache(self, play, refresh=True):
        """Responsible for setting _hosts_cache and _hosts_cache_all
        See comment in ``__init__`` for the purpose of these caches
        """
        if not refresh and all((self._hosts_cache, self._hosts_cache_all)):
            return
        if not play.finalized and Templar(None).is_template(play.hosts):
            _pattern = 'all'
        else:
            _pattern = play.hosts or 'all'
        self._hosts_cache_all = [h.name for h in self._inventory.get_hosts(pattern=_pattern, ignore_restrictions=True)]
        self._hosts_cache = [h.name for h in self._inventory.get_hosts(play.hosts, order=play.order)]
    def cleanup(self):