prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  os.kill is not available in windows before python 2.7
  As per the topic, the current celery implementation (>=2.3.0) crashes on windows using python 2.5 and 2.6, because it uses os.kill which is not available in windows before python 2.7
  
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `celery/concurrency/processes/__init__.py`
  Content:
  ```
  1 """
  2 
  3 Process Pools.
  4 
  5 """
  6 import platform
  7 import signal as _signal
  8 
  9 from os import kill as _kill
  10 
  11 from celery.concurrency.base import BasePool
  12 from celery.concurrency.processes.pool import Pool, RUN
  13 
  14 if platform.system() == "Windows":  # pragma: no cover
  15     # On Windows os.kill calls TerminateProcess which cannot be
  16     # handled by # any process, so this is needed to terminate the task
  17     # *and its children* (if any).
  18     from celery.concurrency.processes import _win
  19     _kill = _win.kill_processtree  # noqa
  20 
  21 
  22 class TaskPool(BasePool):
  23     """Process Pool for processing tasks in parallel.
  24 
  25     :param processes: see :attr:`processes`.
  26     :param logger: see :attr:`logger`.
  27 
  28 
  29     .. attribute:: limit
  30 
  31         The number of processes that can run simultaneously.
  32 
  33     .. attribute:: logger
  34 
  35         The logger used for debugging.
  36 
  37     """
  38     Pool = Pool
  39 
  40     def on_start(self):
  41         """Run the task pool.
  42 
  43         Will pre-fork all workers so they're ready to accept tasks.
  44 
  45         """
  46         self._pool = self.Pool(processes=self.limit, **self.options)
  47         self.on_apply = self._pool.apply_async
  48 
  49     def on_stop(self):
  50         """Gracefully stop the pool."""
  51         if self._pool is not None and self._pool._state == RUN:
  52             self._pool.close()
  53             self._pool.join()
  54             self._pool = None
  55 
  56     def on_terminate(self):
  57         """Force terminate the pool."""
  58         if self._pool is not None:
  59             self._pool.terminate()
  60             self._pool = None
  61 
  62     def terminate_job(self, pid, signal=None):
  63         _kill(pid, signal or _signal.SIGTERM)
  64 
  65     def grow(self, n=1):
  66         return self._pool.grow(n)
  67 
  68     def shrink(self, n=1):
  69         return self._pool.shrink(n)
  70 
  71     def _get_info(self):
  72         return {"max-concurrency": self.limit,
  73                 "processes": [p.pid for p in self._pool._pool],
  74                 "max-tasks-per-child": self._pool._maxtasksperchild,
  75                 "put-guarded-by-semaphore": self.putlocks,
  76                 "timeouts": (self._pool.soft_timeout, self._pool.timeout)}
  77 
  78     @property
  79     def num_processes(self):
  80         return self._pool._processes
  81
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/celery/concurrency/processes/__init__.py b/celery/concurrency/processes/__init__.py
  --- a/celery/concurrency/processes/__init__.py
  +++ b/celery/concurrency/processes/__init__.py
  @@ -6,8 +6,6 @@
   import platform
   import signal as _signal
   
  -from os import kill as _kill
  -
   from celery.concurrency.base import BasePool
   from celery.concurrency.processes.pool import Pool, RUN
   
  @@ -17,6 +15,8 @@
       # *and its children* (if any).
       from celery.concurrency.processes import _win
       _kill = _win.kill_processtree  # noqa
  +else:
  +    from os import kill as _kill
   
   
   class TaskPool(BasePool):
  
verification_info: {"golden_diff": "diff --git a/celery/concurrency/processes/__init__.py b/celery/concurrency/processes/__init__.py\n--- a/celery/concurrency/processes/__init__.py\n+++ b/celery/concurrency/processes/__init__.py\n@@ -6,8 +6,6 @@\n import platform\n import signal as _signal\n \n-from os import kill as _kill\n-\n from celery.concurrency.base import BasePool\n from celery.concurrency.processes.pool import Pool, RUN\n \n@@ -17,6 +15,8 @@\n     # *and its children* (if any).\n     from celery.concurrency.processes import _win\n     _kill = _win.kill_processtree  # noqa\n+else:\n+    from os import kill as _kill\n \n \n class TaskPool(BasePool):\n", "issue": "os.kill is not available in windows before python 2.7\nAs per the topic, the current celery implementation (>=2.3.0) crashes on windows using python 2.5 and 2.6, because it uses os.kill which is not available in windows before python 2.7\n\n", "before_files": [{"content": "\"\"\"\n\nProcess Pools.\n\n\"\"\"\nimport platform\nimport signal as _signal\n\nfrom os import kill as _kill\n\nfrom celery.concurrency.base import BasePool\nfrom celery.concurrency.processes.pool import Pool, RUN\n\nif platform.system() == \"Windows\":  # pragma: no cover\n    # On Windows os.kill calls TerminateProcess which cannot be\n    # handled by # any process, so this is needed to terminate the task\n    # *and its children* (if any).\n    from celery.concurrency.processes import _win\n    _kill = _win.kill_processtree  # noqa\n\n\nclass TaskPool(BasePool):\n    \"\"\"Process Pool for processing tasks in parallel.\n\n    :param processes: see :attr:`processes`.\n    :param logger: see :attr:`logger`.\n\n\n    .. attribute:: limit\n\n        The number of processes that can run simultaneously.\n\n    .. attribute:: logger\n\n        The logger used for debugging.\n\n    \"\"\"\n    Pool = Pool\n\n    def on_start(self):\n        \"\"\"Run the task pool.\n\n        Will pre-fork all workers so they're ready to accept tasks.\n\n        \"\"\"\n        self._pool = self.Pool(processes=self.limit, **self.options)\n        self.on_apply = self._pool.apply_async\n\n    def on_stop(self):\n        \"\"\"Gracefully stop the pool.\"\"\"\n        if self._pool is not None and self._pool._state == RUN:\n            self._pool.close()\n            self._pool.join()\n            self._pool = None\n\n    def on_terminate(self):\n        \"\"\"Force terminate the pool.\"\"\"\n        if self._pool is not None:\n            self._pool.terminate()\n            self._pool = None\n\n    def terminate_job(self, pid, signal=None):\n        _kill(pid, signal or _signal.SIGTERM)\n\n    def grow(self, n=1):\n        return self._pool.grow(n)\n\n    def shrink(self, n=1):\n        return self._pool.shrink(n)\n\n    def _get_info(self):\n        return {\"max-concurrency\": self.limit,\n                \"processes\": [p.pid for p in self._pool._pool],\n                \"max-tasks-per-child\": self._pool._maxtasksperchild,\n                \"put-guarded-by-semaphore\": self.putlocks,\n                \"timeouts\": (self._pool.soft_timeout, self._pool.timeout)}\n\n    @property\n    def num_processes(self):\n        return self._pool._processes\n", "path": "celery/concurrency/processes/__init__.py"}], "after_files": [{"content": "\"\"\"\n\nProcess Pools.\n\n\"\"\"\nimport platform\nimport signal as _signal\n\nfrom celery.concurrency.base import BasePool\nfrom celery.concurrency.processes.pool import Pool, RUN\n\nif platform.system() == \"Windows\":  # pragma: no cover\n    # On Windows os.kill calls TerminateProcess which cannot be\n    # handled by # any process, so this is needed to terminate the task\n    # *and its children* (if any).\n    from celery.concurrency.processes import _win\n    _kill = _win.kill_processtree  # noqa\nelse:\n    from os import kill as _kill\n\n\nclass TaskPool(BasePool):\n    \"\"\"Process Pool for processing tasks in parallel.\n\n    :param processes: see :attr:`processes`.\n    :param logger: see :attr:`logger`.\n\n\n    .. attribute:: limit\n\n        The number of processes that can run simultaneously.\n\n    .. attribute:: logger\n\n        The logger used for debugging.\n\n    \"\"\"\n    Pool = Pool\n\n    def on_start(self):\n        \"\"\"Run the task pool.\n\n        Will pre-fork all workers so they're ready to accept tasks.\n\n        \"\"\"\n        self._pool = self.Pool(processes=self.limit, **self.options)\n        self.on_apply = self._pool.apply_async\n\n    def on_stop(self):\n        \"\"\"Gracefully stop the pool.\"\"\"\n        if self._pool is not None and self._pool._state == RUN:\n            self._pool.close()\n            self._pool.join()\n            self._pool = None\n\n    def on_terminate(self):\n        \"\"\"Force terminate the pool.\"\"\"\n        if self._pool is not None:\n            self._pool.terminate()\n            self._pool = None\n\n    def terminate_job(self, pid, signal=None):\n        _kill(pid, signal or _signal.SIGTERM)\n\n    def grow(self, n=1):\n        return self._pool.grow(n)\n\n    def shrink(self, n=1):\n        return self._pool.shrink(n)\n\n    def _get_info(self):\n        return {\"max-concurrency\": self.limit,\n                \"processes\": [p.pid for p in self._pool._pool],\n                \"max-tasks-per-child\": self._pool._maxtasksperchild,\n                \"put-guarded-by-semaphore\": self.putlocks,\n                \"timeouts\": (self._pool.soft_timeout, self._pool.timeout)}\n\n    @property\n    def num_processes(self):\n        return self._pool._processes\n", "path": "celery/concurrency/processes/__init__.py"}]}