尝试在 Python 3.7 中运行 Jupyter 时出现关于异步的 SyntaxError

Question

在尝试在 Python 3.7 上启动 Jupyter 时，我观察到以下情况：

$ jupyter notebook
Traceback (most recent call last):
  File "/usr/local/bin/jupyter-notebook", line 11, in <module>
    sys.exit(main())
  File "/usr/local/lib/python3.7/dist-packages/jupyter_core/application.py", line 266, in launch_instance
    return super(JupyterApp, cls).launch_instance(argv=argv, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/traitlets/config/application.py", line 657, in launch_instance
    app.initialize(argv)
  File "<decorator-gen-7>", line 2, in initialize
  File "/usr/local/lib/python3.7/dist-packages/traitlets/config/application.py", line 87, in catch_config_error
    return method(app, *args, **kwargs)
  File "/usr/local/lib/python3.7/dist-packages/notebook/notebookapp.py", line 1629, in initialize
    self.init_webapp()
  File "/usr/local/lib/python3.7/dist-packages/notebook/notebookapp.py", line 1379, in init_webapp
    self.jinja_environment_options,
  File "/usr/local/lib/python3.7/dist-packages/notebook/notebookapp.py", line 158, in __init__
    default_url, settings_overrides, jinja_env_options)
  File "/usr/local/lib/python3.7/dist-packages/notebook/notebookapp.py", line 270, in init_settings
    nbextensions_path=jupyter_app.nbextensions_path,
  File "/usr/local/lib/python3.7/dist-packages/notebook/notebookapp.py", line 1066, in nbextensions_path
    from IPython.paths import get_ipython_dir
  File "/usr/local/lib/python3.7/dist-packages/IPython/__init__.py", line 54, in <module>
    from .core.application import Application
  File "/usr/local/lib/python3.7/dist-packages/IPython/core/application.py", line 25, in <module>
    from IPython.core import release, crashhandler
  File "/usr/local/lib/python3.7/dist-packages/IPython/core/crashhandler.py", line 27, in <module>
    from IPython.core import ultratb
  File "/usr/local/lib/python3.7/dist-packages/IPython/core/ultratb.py", line 119, in <module>
    from IPython.utils import path as util_path
  File "/usr/local/lib/python3.7/dist-packages/IPython/utils/path.py", line 17, in <module>
    from IPython.utils.process import system
  File "/usr/local/lib/python3.7/dist-packages/IPython/utils/process.py", line 19, in <module>
    from ._process_posix import system, getoutput, arg_split, check_pid
  File "/usr/local/lib/python3.7/dist-packages/IPython/utils/_process_posix.py", line 23, in <module>
    import pexpect
  File "/usr/lib/python3/dist-packages/pexpect/__init__.py", line 75, in <module>
    from .pty_spawn import spawn, spawnu
  File "/usr/lib/python3/dist-packages/pexpect/pty_spawn.py", line 15, in <module>
    from .spawnbase import SpawnBase
  File "/usr/lib/python3/dist-packages/pexpect/spawnbase.py", line 218
    def expect(self, pattern, timeout=-1, searchwindowsize=-1, async=False):
                                                                   ^
SyntaxError: invalid syntax

我已经安装python3.7-distutils（似乎有功能pexpect）并且我已经使用 重新安装了 Jupyter pip3，但我仍然看到这个错误。我还卸载并重新安装了以下软件包：

python3.7 python3.7-dev python3.7-distutils python3.7-tk

应该做什么？

我看到对此修复程序的引用，但假设它是一个修复程序，不知道如何在此 16.04 LTS 安装上启动并运行它。

---

编辑：pexpect在 Python 3.7 中导入时，我得到了同样的东西：

>>> import pexpect
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3/dist-packages/pexpect/__init__.py", line 75, in <module>
    from .pty_spawn import spawn, spawnu
  File "/usr/lib/python3/dist-packages/pexpect/pty_spawn.py", line 15, in <module>
    from .spawnbase import SpawnBase
  File "/usr/lib/python3/dist-packages/pexpect/spawnbase.py", line 218
    def expect(self, pattern, timeout=-1, searchwindowsize=-1, async=False):
                                                                   ^
SyntaxError: invalid syntax

Answer 1

对我来说，它与 apt-get 安装的 python3 冲突，所以我必须先卸载它/它们：

sudo apt-get remove python-pexpect python3-pexpect

进而

sudo pip3.7 install --upgrade pexpect

Answer 2

我在运行 django 测试时遇到了这个问题。升级到当时最新版本（4.8），修复了问题。