prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  [BUG] Cannot import new_client
  **Describe the bug**
  When trying to import ``new_client`` from ``mars.actors`` in Python 2.7 in Linux, a ValueError is raised:
  
  ```
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
    File "mars/actors/core.pyx", line 147, in mars.actors.core.new_client
      cpdef object new_client(object parallel=None, str backend='gevent'):
    File "mars/actors/core.pyx", line 151, in mars.actors.core.new_client
      from .pool.gevent_pool import ActorClient
    File "mars/actors/pool/gevent_pool.pyx", line 38, in init mars.actors.pool.gevent_pool
      from ...lib import gipc
    File "mars/lib/gipc.pyx", line 1159, in init mars.lib.gipc
      __exec("""def _reraise(tp, value, tb=None):
    File "mars/lib/gipc.pyx", line 1150, in mars.lib.gipc.__exec
      frame = sys._getframe(1)
  ValueError: call stack is not deep enough
  ```
  
  **To Reproduce**
  ```python
  >>> from mars.actors import new_client
  >>> client = new_client()
  ```
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `mars/actors/__init__.py`
  Content:
  ```
  1 #!/usr/bin/env python
  2 # -*- coding: utf-8 -*-
  3 # Copyright 1999-2018 Alibaba Group Holding Ltd.
  4 #
  5 # Licensed under the Apache License, Version 2.0 (the "License");
  6 # you may not use this file except in compliance with the License.
  7 # You may obtain a copy of the License at
  8 #
  9 #      http://www.apache.org/licenses/LICENSE-2.0
  10 #
  11 # Unless required by applicable law or agreed to in writing, software
  12 # distributed under the License is distributed on an "AS IS" BASIS,
  13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14 # See the License for the specific language governing permissions and
  15 # limitations under the License.
  16 
  17 
  18 from .core import create_actor_pool, Actor, FunctionActor, new_client, \
  19     register_actor_implementation, unregister_actor_implementation
  20 from .errors import ActorPoolNotStarted, ActorNotExist, ActorAlreadyExist
  21 from .distributor import Distributor
  22
  ```
  --- 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/mars/actors/__init__.py b/mars/actors/__init__.py
  --- a/mars/actors/__init__.py
  +++ b/mars/actors/__init__.py
  @@ -14,8 +14,14 @@
   # See the License for the specific language governing permissions and
   # limitations under the License.
   
  -
   from .core import create_actor_pool, Actor, FunctionActor, new_client, \
       register_actor_implementation, unregister_actor_implementation
   from .errors import ActorPoolNotStarted, ActorNotExist, ActorAlreadyExist
   from .distributor import Distributor
  +
  +# import gipc first to avoid stack issue of `call stack is not deep enough`
  +try:
  +    from ..lib import gipc
  +    del gipc
  +except ImportError:  # pragma: no cover
  +    pass
  
verification_info: {"golden_diff": "diff --git a/mars/actors/__init__.py b/mars/actors/__init__.py\n--- a/mars/actors/__init__.py\n+++ b/mars/actors/__init__.py\n@@ -14,8 +14,14 @@\n # See the License for the specific language governing permissions and\n # limitations under the License.\n \n-\n from .core import create_actor_pool, Actor, FunctionActor, new_client, \\\n     register_actor_implementation, unregister_actor_implementation\n from .errors import ActorPoolNotStarted, ActorNotExist, ActorAlreadyExist\n from .distributor import Distributor\n+\n+# import gipc first to avoid stack issue of `call stack is not deep enough`\n+try:\n+    from ..lib import gipc\n+    del gipc\n+except ImportError:  # pragma: no cover\n+    pass\n", "issue": "[BUG] Cannot import new_client\n**Describe the bug**\r\nWhen trying to import ``new_client`` from ``mars.actors`` in Python 2.7 in Linux, a ValueError is raised:\r\n\r\n```\r\nTraceback (most recent call last):\r\n  File \"<stdin>\", line 1, in <module>\r\n  File \"mars/actors/core.pyx\", line 147, in mars.actors.core.new_client\r\n    cpdef object new_client(object parallel=None, str backend='gevent'):\r\n  File \"mars/actors/core.pyx\", line 151, in mars.actors.core.new_client\r\n    from .pool.gevent_pool import ActorClient\r\n  File \"mars/actors/pool/gevent_pool.pyx\", line 38, in init mars.actors.pool.gevent_pool\r\n    from ...lib import gipc\r\n  File \"mars/lib/gipc.pyx\", line 1159, in init mars.lib.gipc\r\n    __exec(\"\"\"def _reraise(tp, value, tb=None):\r\n  File \"mars/lib/gipc.pyx\", line 1150, in mars.lib.gipc.__exec\r\n    frame = sys._getframe(1)\r\nValueError: call stack is not deep enough\r\n```\r\n\r\n**To Reproduce**\r\n```python\r\n>>> from mars.actors import new_client\r\n>>> client = new_client()\r\n```\n", "before_files": [{"content": "#!/usr/bin/env python\n# -*- coding: utf-8 -*-\n# Copyright 1999-2018 Alibaba Group Holding Ltd.\n#\n# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#      http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\n\nfrom .core import create_actor_pool, Actor, FunctionActor, new_client, \\\n    register_actor_implementation, unregister_actor_implementation\nfrom .errors import ActorPoolNotStarted, ActorNotExist, ActorAlreadyExist\nfrom .distributor import Distributor\n", "path": "mars/actors/__init__.py"}], "after_files": [{"content": "#!/usr/bin/env python\n# -*- coding: utf-8 -*-\n# Copyright 1999-2018 Alibaba Group Holding Ltd.\n#\n# Licensed under the Apache License, Version 2.0 (the \"License\");\n# you may not use this file except in compliance with the License.\n# You may obtain a copy of the License at\n#\n#      http://www.apache.org/licenses/LICENSE-2.0\n#\n# Unless required by applicable law or agreed to in writing, software\n# distributed under the License is distributed on an \"AS IS\" BASIS,\n# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n# See the License for the specific language governing permissions and\n# limitations under the License.\n\nfrom .core import create_actor_pool, Actor, FunctionActor, new_client, \\\n    register_actor_implementation, unregister_actor_implementation\nfrom .errors import ActorPoolNotStarted, ActorNotExist, ActorAlreadyExist\nfrom .distributor import Distributor\n\n# import gipc first to avoid stack issue of `call stack is not deep enough`\ntry:\n    from ..lib import gipc\n    del gipc\nexcept ImportError:  # pragma: no cover\n    pass\n", "path": "mars/actors/__init__.py"}]}