code: def push(self, key: str, x: bool):
      self.assert_valid()
      if key in self._seen:
          return
      while len(self._q) >= self._window_size:
          old_key, old = self._q.popleft()
          self._seen.remove(old_key)
          if old:
              self._n_true -= 1
      self._q.append((key, x))
      self._seen.add(key)
      if x:
          self._n_true += 1
      self.assert_valid()
  
imports: import json
  import logging
  from collections import deque
  from functools import wraps
  from typing import Any, Deque, Dict, List, Optional, Set, Tuple, overload
  from aiohttp import web
  from gear import Database, maybe_parse_bearer_header
  from hailtop.utils import secret_alnum_string
label_desc: Use image node_id 3 for calling the WindowFractionCounter obj's underlying member method code with example usage: obj.push(key, x) without return types