C:\Users\WQBin>jupyter lab

[I ::44.340 LabApp] [nb_conda_kernels] enabled,  kernels found

[I ::44.883 LabApp] [jupyter_nbextensions_configurator] enabled 0.4.

No cio_test package found.

[I ::45.137 LabApp] [nb_anacondacloud] enabled

[I ::45.142 LabApp] [nb_conda] enabled

[I ::45.245 LabApp] \u2713 nbpresent HTML export ENABLED

[W ::45.245 LabApp] \u2717 nbpresent PDF export DISABLED: No module named 'nbbrowserpdf'

[W ::45.248 LabApp] JupyterLab server extension not enabled, manually loading...

[I ::45.254 LabApp] JupyterLab extension loaded from D:\Program Files\Anaconda3\lib\site-packages\jupyterlab

[I ::45.254 LabApp] JupyterLab application directory is D:\Program Files\Anaconda3\share\jupyter\lab

[I ::45.713 LabApp] Serving notebooks from local directory: C:\Users\WQBin

[I ::45.713 LabApp]  active kernels

[I ::45.713 LabApp] The Jupyter Notebook is running at: http://localhost:8888/?token=8c96871108852e9fae719175bd349d6c639e565734c17a40

[I ::45.714 LabApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).

[C ::45.715 LabApp]

    Copy/paste this URL into your browser when you connect for the first time,

    to login with a token:

        http://localhost:8888/?token=8c96871108852e9fae719175bd349d6c639e565734c17a40

[I ::46.235 LabApp] Accepting one-time-token-authenticated connection from ::

[I ::47.030 LabApp]  GET /lab/workspaces/auto-q/?clone (::) .00ms

[W ::47.484 LabApp]  GET /metrics? (::) .64ms referer=http://localhost:8888/lab/workspaces/auto-q?clone

[W ::47.614 LabApp] Could not determine jupyterlab build status without nodejs

[I ::49.448 LabApp] Kernel started: fb69b5ba-b6c1-41c5--23cc7798abd5

[I ::49.514 LabApp] Kernel started: 758b81c3-c673-4a35-b0bf-41cd0fc1046e

[I ::49.559 LabApp] Kernel started: b1fbfcc1-60ae-4e3a-88c1-61b941b9dce3

[I ::49.607 LabApp] Kernel started: 404e2a28-8ab6-413e--2fc6fed625a7

Traceback (most recent call last):

  File "D:\Program Files\Anaconda3\envs\py36\lib\runpy.py", line , in _run_module_as_main

    "__main__", mod_spec)

  File "D:\Program Files\Anaconda3\envs\py36\lib\runpy.py", line , in _run_code

    exec(code, run_globals)

  File "D:\Program Files\Anaconda3\envs\py36\lib\site-packages\ipykernel\__main__.py", line , in <module>

    app.launch_new_instance()

  File "D:\Program Files\Anaconda3\envs\py36\lib\site-packages\traitlets\config\application.py", line , in launch_instance

    app.start()

  File "D:\Program Files\Anaconda3\envs\py36\lib\site-packages\ipykernel\kernelapp.py", line , in start

    ioloop.IOLoop.instance().start()

  File "D:\Program Files\Anaconda3\envs\py36\lib\site-packages\tornado\platform\asyncio.py", line , in start

    self.asyncio_loop.run_forever()

  File "D:\Program Files\Anaconda3\envs\py36\lib\asyncio\base_events.py", line , in run_forever

    raise RuntimeError('This event loop is already running')

RuntimeError: This event loop is already running

(D:\Program Files\Anaconda3) C:\Users\WQBin>conda install -c anaconda-nb-extensions nbbrowserpdf

Fetching package metadata .................

Solving package specifications: .

Package plan for installation in environment D:\Program Files\Anaconda3:

The following NEW packages will be INSTALLED:

    ghost.py:          0.2.-py35_0  anaconda-nb-extensions

    nb_config_manager: 0.1.-py35_0  anaconda-nb-extensions

    nbbrowserpdf:      0.2.-py35_0  anaconda-nb-extensions

    pypdf2:            1.25.-py35_0 anaconda-nb-extensions

Proceed ([y]/n)? y

ghost.py-0.2. % |###############################| Time: :: 181.75 kB/s

pypdf2-1.25.- % |###############################| Time: :: 371.89 kB/s

nb_config_mana % |###############################| Time: ::   1.24 MB/s

nbbrowserpdf- % |###############################| Time: ::   1.67 MB/s