We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
import error
ray 0.8.5,when I try to use ray， it occurs  Ray must be imported before pickle5 because Ray requires a specific version of pickle5 (which is packaged along with Ray.

I want to know it must import  pickle5 before import ray,  Right?

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `python/ray/__init__.py`
Content:
```
1 import os
2 import logging
3 from os.path import dirname
4 import sys
5 
6 logger = logging.getLogger(__name__)
7 
8 # MUST add pickle5 to the import path because it will be imported by some
9 # raylet modules.
10 
11 if "pickle5" in sys.modules:
12     raise ImportError("Ray must be imported before pickle5 because Ray "
13                       "requires a specific version of pickle5 (which is "
14                       "packaged along with Ray).")
15 
16 if "OMP_NUM_THREADS" not in os.environ:
17     logger.debug("[ray] Forcing OMP_NUM_THREADS=1 to avoid performance "
18                  "degradation with many workers (issue #6998). You can "
19                  "override this by explicitly setting OMP_NUM_THREADS.")
20     os.environ["OMP_NUM_THREADS"] = "1"
21 
22 # Add the directory containing pickle5 to the Python path so that we find the
23 # pickle5 version packaged with ray and not a pre-existing pickle5.
24 pickle5_path = os.path.join(
25     os.path.abspath(os.path.dirname(__file__)), "pickle5_files")
26 sys.path.insert(0, pickle5_path)
27 
28 # Importing psutil & setproctitle. Must be before ray._raylet is initialized.
29 thirdparty_files = os.path.join(
30     os.path.abspath(os.path.dirname(__file__)), "thirdparty_files")
31 sys.path.insert(0, thirdparty_files)
32 
33 if sys.platform == "win32":
34     import ray.compat  # noqa: E402
35     ray.compat.patch_redis_empty_recv()
36 
37 # Expose ray ABI symbols which may be dependent by other shared
38 # libraries such as _streaming.so. See BUILD.bazel:_raylet
39 python_shared_lib_suffix = ".so" if sys.platform != "win32" else ".pyd"
40 so_path = os.path.join(dirname(__file__), "_raylet" + python_shared_lib_suffix)
41 if os.path.exists(so_path):
42     import ctypes
43     from ctypes import CDLL
44     CDLL(so_path, ctypes.RTLD_GLOBAL)
45 
46 import ray._raylet  # noqa: E402
47 
48 from ray._raylet import (
49     ActorCheckpointID,
50     ActorClassID,
51     ActorID,
52     ClientID,
53     Config as _Config,
54     JobID,
55     WorkerID,
56     FunctionID,
57     ObjectID,
58     TaskID,
59     UniqueID,
60     Language,
61 )  # noqa: E402
62 
63 _config = _Config()
64 
65 from ray.profiling import profile  # noqa: E402
66 from ray.state import (jobs, nodes, actors, objects, timeline,
67                        object_transfer_timeline, cluster_resources,
68                        available_resources, errors)  # noqa: E402
69 from ray.worker import (
70     LOCAL_MODE,
71     SCRIPT_MODE,
72     WORKER_MODE,
73     cancel,
74     connect,
75     disconnect,
76     get,
77     get_gpu_ids,
78     get_resource_ids,
79     get_webui_url,
80     init,
81     is_initialized,
82     put,
83     kill,
84     register_custom_serializer,
85     remote,
86     shutdown,
87     show_in_webui,
88     wait,
89 )  # noqa: E402
90 import ray.internal  # noqa: E402
91 import ray.projects  # noqa: E402
92 # We import ray.actor because some code is run in actor.py which initializes
93 # some functions in the worker.
94 import ray.actor  # noqa: F401
95 from ray.actor import method  # noqa: E402
96 from ray.cross_language import java_function, java_actor_class  # noqa: E402
97 from ray import util  # noqa: E402
98 
99 # Replaced with the current commit when building the wheels.
100 __commit__ = "{{RAY_COMMIT_SHA}}"
101 __version__ = "0.9.0.dev0"
102 
103 __all__ = [
104     "jobs",
105     "nodes",
106     "actors",
107     "objects",
108     "timeline",
109     "object_transfer_timeline",
110     "cluster_resources",
111     "available_resources",
112     "errors",
113     "LOCAL_MODE",
114     "PYTHON_MODE",
115     "SCRIPT_MODE",
116     "WORKER_MODE",
117     "__version__",
118     "_config",
119     "_get_runtime_context",
120     "actor",
121     "cancel",
122     "connect",
123     "disconnect",
124     "get",
125     "get_gpu_ids",
126     "get_resource_ids",
127     "get_webui_url",
128     "init",
129     "internal",
130     "is_initialized",
131     "method",
132     "profile",
133     "projects",
134     "put",
135     "kill",
136     "register_custom_serializer",
137     "remote",
138     "shutdown",
139     "show_in_webui",
140     "wait",
141     "Language",
142     "java_function",
143     "java_actor_class",
144     "util",
145 ]
146 
147 # ID types
148 __all__ += [
149     "ActorCheckpointID",
150     "ActorClassID",
151     "ActorID",
152     "ClientID",
153     "JobID",
154     "WorkerID",
155     "FunctionID",
156     "ObjectID",
157     "TaskID",
158     "UniqueID",
159 ]
160
```
--- 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()

```

diff --git a/python/ray/__init__.py b/python/ray/__init__.py
--- a/python/ray/__init__.py
+++ b/python/ray/__init__.py
@@ -9,9 +9,13 @@
 # raylet modules.
 
 if "pickle5" in sys.modules:
-    raise ImportError("Ray must be imported before pickle5 because Ray "
-                      "requires a specific version of pickle5 (which is "
-                      "packaged along with Ray).")
+    import pkg_resources
+    version_info = pkg_resources.require("pickle5")
+    version = tuple(int(n) for n in version_info[0].version.split("."))
+    if version < (0, 0, 10):
+        raise ImportError("You are using an old version of pickle5 that "
+                          "leaks memory, please run 'pip install pickle5 -U' "
+                          "to upgrade")
 
 if "OMP_NUM_THREADS" not in os.environ:
     logger.debug("[ray] Forcing OMP_NUM_THREADS=1 to avoid performance "

{"golden_diff": "diff --git a/python/ray/__init__.py b/python/ray/__init__.py\n--- a/python/ray/__init__.py\n+++ b/python/ray/__init__.py\n@@ -9,9 +9,13 @@\n # raylet modules.\n \n if \"pickle5\" in sys.modules:\n-    raise ImportError(\"Ray must be imported before pickle5 because Ray \"\n-                      \"requires a specific version of pickle5 (which is \"\n-                      \"packaged along with Ray).\")\n+    import pkg_resources\n+    version_info = pkg_resources.require(\"pickle5\")\n+    version = tuple(int(n) for n in version_info[0].version.split(\".\"))\n+    if version < (0, 0, 10):\n+        raise ImportError(\"You are using an old version of pickle5 that \"\n+                          \"leaks memory, please run 'pip install pickle5 -U' \"\n+                          \"to upgrade\")\n \n if \"OMP_NUM_THREADS\" not in os.environ:\n     logger.debug(\"[ray] Forcing OMP_NUM_THREADS=1 to avoid performance \"\n", "issue": "import error\nray 0.8.5,when I try to use ray\uff0c it occurs  Ray must be imported before pickle5 because Ray requires a specific version of pickle5 (which is packaged along with Ray.\r\n\r\nI want to know it must import  pickle5 before import ray,  Right?\n", "before_files": [{"content": "import os\nimport logging\nfrom os.path import dirname\nimport sys\n\nlogger = logging.getLogger(__name__)\n\n# MUST add pickle5 to the import path because it will be imported by some\n# raylet modules.\n\nif \"pickle5\" in sys.modules:\n    raise ImportError(\"Ray must be imported before pickle5 because Ray \"\n                      \"requires a specific version of pickle5 (which is \"\n                      \"packaged along with Ray).\")\n\nif \"OMP_NUM_THREADS\" not in os.environ:\n    logger.debug(\"[ray] Forcing OMP_NUM_THREADS=1 to avoid performance \"\n                 \"degradation with many workers (issue #6998). You can \"\n                 \"override this by explicitly setting OMP_NUM_THREADS.\")\n    os.environ[\"OMP_NUM_THREADS\"] = \"1\"\n\n# Add the directory containing pickle5 to the Python path so that we find the\n# pickle5 version packaged with ray and not a pre-existing pickle5.\npickle5_path = os.path.join(\n    os.path.abspath(os.path.dirname(__file__)), \"pickle5_files\")\nsys.path.insert(0, pickle5_path)\n\n# Importing psutil & setproctitle. Must be before ray._raylet is initialized.\nthirdparty_files = os.path.join(\n    os.path.abspath(os.path.dirname(__file__)), \"thirdparty_files\")\nsys.path.insert(0, thirdparty_files)\n\nif sys.platform == \"win32\":\n    import ray.compat  # noqa: E402\n    ray.compat.patch_redis_empty_recv()\n\n# Expose ray ABI symbols which may be dependent by other shared\n# libraries such as _streaming.so. See BUILD.bazel:_raylet\npython_shared_lib_suffix = \".so\" if sys.platform != \"win32\" else \".pyd\"\nso_path = os.path.join(dirname(__file__), \"_raylet\" + python_shared_lib_suffix)\nif os.path.exists(so_path):\n    import ctypes\n    from ctypes import CDLL\n    CDLL(so_path, ctypes.RTLD_GLOBAL)\n\nimport ray._raylet  # noqa: E402\n\nfrom ray._raylet import (\n    ActorCheckpointID,\n    ActorClassID,\n    ActorID,\n    ClientID,\n    Config as _Config,\n    JobID,\n    WorkerID,\n    FunctionID,\n    ObjectID,\n    TaskID,\n    UniqueID,\n    Language,\n)  # noqa: E402\n\n_config = _Config()\n\nfrom ray.profiling import profile  # noqa: E402\nfrom ray.state import (jobs, nodes, actors, objects, timeline,\n                       object_transfer_timeline, cluster_resources,\n                       available_resources, errors)  # noqa: E402\nfrom ray.worker import (\n    LOCAL_MODE,\n    SCRIPT_MODE,\n    WORKER_MODE,\n    cancel,\n    connect,\n    disconnect,\n    get,\n    get_gpu_ids,\n    get_resource_ids,\n    get_webui_url,\n    init,\n    is_initialized,\n    put,\n    kill,\n    register_custom_serializer,\n    remote,\n    shutdown,\n    show_in_webui,\n    wait,\n)  # noqa: E402\nimport ray.internal  # noqa: E402\nimport ray.projects  # noqa: E402\n# We import ray.actor because some code is run in actor.py which initializes\n# some functions in the worker.\nimport ray.actor  # noqa: F401\nfrom ray.actor import method  # noqa: E402\nfrom ray.cross_language import java_function, java_actor_class  # noqa: E402\nfrom ray import util  # noqa: E402\n\n# Replaced with the current commit when building the wheels.\n__commit__ = \"{{RAY_COMMIT_SHA}}\"\n__version__ = \"0.9.0.dev0\"\n\n__all__ = [\n    \"jobs\",\n    \"nodes\",\n    \"actors\",\n    \"objects\",\n    \"timeline\",\n    \"object_transfer_timeline\",\n    \"cluster_resources\",\n    \"available_resources\",\n    \"errors\",\n    \"LOCAL_MODE\",\n    \"PYTHON_MODE\",\n    \"SCRIPT_MODE\",\n    \"WORKER_MODE\",\n    \"__version__\",\n    \"_config\",\n    \"_get_runtime_context\",\n    \"actor\",\n    \"cancel\",\n    \"connect\",\n    \"disconnect\",\n    \"get\",\n    \"get_gpu_ids\",\n    \"get_resource_ids\",\n    \"get_webui_url\",\n    \"init\",\n    \"internal\",\n    \"is_initialized\",\n    \"method\",\n    \"profile\",\n    \"projects\",\n    \"put\",\n    \"kill\",\n    \"register_custom_serializer\",\n    \"remote\",\n    \"shutdown\",\n    \"show_in_webui\",\n    \"wait\",\n    \"Language\",\n    \"java_function\",\n    \"java_actor_class\",\n    \"util\",\n]\n\n# ID types\n__all__ += [\n    \"ActorCheckpointID\",\n    \"ActorClassID\",\n    \"ActorID\",\n    \"ClientID\",\n    \"JobID\",\n    \"WorkerID\",\n    \"FunctionID\",\n    \"ObjectID\",\n    \"TaskID\",\n    \"UniqueID\",\n]\n", "path": "python/ray/__init__.py"}], "after_files": [{"content": "import os\nimport logging\nfrom os.path import dirname\nimport sys\n\nlogger = logging.getLogger(__name__)\n\n# MUST add pickle5 to the import path because it will be imported by some\n# raylet modules.\n\nif \"pickle5\" in sys.modules:\n    import pkg_resources\n    version_info = pkg_resources.require(\"pickle5\")\n    version = tuple(int(n) for n in version_info[0].version.split(\".\"))\n    if version < (0, 0, 10):\n        raise ImportError(\"You are using an old version of pickle5 that \"\n                          \"leaks memory, please run 'pip install pickle5 -U' \"\n                          \"to upgrade\")\n\nif \"OMP_NUM_THREADS\" not in os.environ:\n    logger.debug(\"[ray] Forcing OMP_NUM_THREADS=1 to avoid performance \"\n                 \"degradation with many workers (issue #6998). You can \"\n                 \"override this by explicitly setting OMP_NUM_THREADS.\")\n    os.environ[\"OMP_NUM_THREADS\"] = \"1\"\n\n# Add the directory containing pickle5 to the Python path so that we find the\n# pickle5 version packaged with ray and not a pre-existing pickle5.\npickle5_path = os.path.join(\n    os.path.abspath(os.path.dirname(__file__)), \"pickle5_files\")\nsys.path.insert(0, pickle5_path)\n\n# Importing psutil & setproctitle. Must be before ray._raylet is initialized.\nthirdparty_files = os.path.join(\n    os.path.abspath(os.path.dirname(__file__)), \"thirdparty_files\")\nsys.path.insert(0, thirdparty_files)\n\nif sys.platform == \"win32\":\n    import ray.compat  # noqa: E402\n    ray.compat.patch_redis_empty_recv()\n\n# Expose ray ABI symbols which may be dependent by other shared\n# libraries such as _streaming.so. See BUILD.bazel:_raylet\npython_shared_lib_suffix = \".so\" if sys.platform != \"win32\" else \".pyd\"\nso_path = os.path.join(dirname(__file__), \"_raylet\" + python_shared_lib_suffix)\nif os.path.exists(so_path):\n    import ctypes\n    from ctypes import CDLL\n    CDLL(so_path, ctypes.RTLD_GLOBAL)\n\nimport ray._raylet  # noqa: E402\n\nfrom ray._raylet import (\n    ActorCheckpointID,\n    ActorClassID,\n    ActorID,\n    ClientID,\n    Config as _Config,\n    JobID,\n    WorkerID,\n    FunctionID,\n    ObjectID,\n    TaskID,\n    UniqueID,\n    Language,\n)  # noqa: E402\n\n_config = _Config()\n\nfrom ray.profiling import profile  # noqa: E402\nfrom ray.state import (jobs, nodes, actors, objects, timeline,\n                       object_transfer_timeline, cluster_resources,\n                       available_resources, errors)  # noqa: E402\nfrom ray.worker import (\n    LOCAL_MODE,\n    SCRIPT_MODE,\n    WORKER_MODE,\n    cancel,\n    connect,\n    disconnect,\n    get,\n    get_gpu_ids,\n    get_resource_ids,\n    get_webui_url,\n    init,\n    is_initialized,\n    put,\n    kill,\n    register_custom_serializer,\n    remote,\n    shutdown,\n    show_in_webui,\n    wait,\n)  # noqa: E402\nimport ray.internal  # noqa: E402\nimport ray.projects  # noqa: E402\n# We import ray.actor because some code is run in actor.py which initializes\n# some functions in the worker.\nimport ray.actor  # noqa: F401\nfrom ray.actor import method  # noqa: E402\nfrom ray.cross_language import java_function, java_actor_class  # noqa: E402\nfrom ray import util  # noqa: E402\n\n# Replaced with the current commit when building the wheels.\n__commit__ = \"{{RAY_COMMIT_SHA}}\"\n__version__ = \"0.9.0.dev0\"\n\n__all__ = [\n    \"jobs\",\n    \"nodes\",\n    \"actors\",\n    \"objects\",\n    \"timeline\",\n    \"object_transfer_timeline\",\n    \"cluster_resources\",\n    \"available_resources\",\n    \"errors\",\n    \"LOCAL_MODE\",\n    \"PYTHON_MODE\",\n    \"SCRIPT_MODE\",\n    \"WORKER_MODE\",\n    \"__version__\",\n    \"_config\",\n    \"_get_runtime_context\",\n    \"actor\",\n    \"cancel\",\n    \"connect\",\n    \"disconnect\",\n    \"get\",\n    \"get_gpu_ids\",\n    \"get_resource_ids\",\n    \"get_webui_url\",\n    \"init\",\n    \"internal\",\n    \"is_initialized\",\n    \"method\",\n    \"profile\",\n    \"projects\",\n    \"put\",\n    \"kill\",\n    \"register_custom_serializer\",\n    \"remote\",\n    \"shutdown\",\n    \"show_in_webui\",\n    \"wait\",\n    \"Language\",\n    \"java_function\",\n    \"java_actor_class\",\n    \"util\",\n]\n\n# ID types\n__all__ += [\n    \"ActorCheckpointID\",\n    \"ActorClassID\",\n    \"ActorID\",\n    \"ClientID\",\n    \"JobID\",\n    \"WorkerID\",\n    \"FunctionID\",\n    \"ObjectID\",\n    \"TaskID\",\n    \"UniqueID\",\n]\n", "path": "python/ray/__init__.py"}]}