当终端和Anaconda Nav无法打开时，如何修复“ Jupyter Notebook”？

Question

自从我改用Spyder以来，大约一年都没有使用Jupyter笔记本。在我更新到最新版本（5.7.8）之前，它一直运行良好。每次我尝试通过Anaconda打开它时，它首先都会启动，但浏览器不会显示。我在终端上运行了“ jupyter笔记本”，并且收到了以下输出：

leonardos-Air:~ Leonardo$ jupyter notebook
Traceback (most recent call last):
  File "/Users/Leonardo/anaconda2/bin/jupyter-notebook", line 7, in <module>
    from notebook.notebookapp import main
  File "/Users/Leonardo/anaconda2/lib/python2.7/site-packages/notebook/notebookapp.py", line 62, in <module>
    from tornado import httpserver
  File "/Users/Leonardo/anaconda2/lib/python2.7/site-packages/tornado/httpserver.py", line 33, in <module>
    from tornado.http1connection import HTTP1ServerConnection, HTTP1ConnectionParameters
  File "/Users/Leonardo/anaconda2/lib/python2.7/site-packages/tornado/http1connection.py", line 30, in <module>
    from tornado import iostream
  File "/Users/Leonardo/anaconda2/lib/python2.7/site-packages/tornado/iostream.py", line 40, in <module>
    from tornado.netutil import ssl_wrap_socket, _client_ssl_defaults, _server_ssl_defaults
  File "/Users/Leonardo/anaconda2/lib/python2.7/site-packages/tornado/netutil.py", line 44, in <module>
    _client_ssl_defaults = ssl.create_default_context(
AttributeError: 'module' object has no attribute 'create_default_context'
leonardos-Air:~ Leonardo$ 

我甚至到处寻找Github的帮助，但无处可寻。请帮忙。