ImportError: cannot import name '_wsgi_encoding_dance' from 'werkzeug._internal'

Question

I am currently running a python code on jupyter notebook. Its a basic dash app tutorial I pulled from the dash documentation. I checked the source code and its up to date (running werkzeug version 2.1.1)

app = Dash(__name__)

df = pd.DataFrame({
    "Fruit": ["Apples", "Oranges", "Bananas", "Apples", "Oranges", "Bananas"],
    "Amount": [4, 1, 2, 2, 4, 5],
    "City": ["SF", "SF", "SF", "Montreal", "Montreal", "Montreal"]
    })

fig = px.bar(df, x="Fruit", y="Amount", color="City", barmode="group")


app.layout = html.Div(children=[
    html.H1(children='Hello Dash'),

    html.Div(children='''
        Dash: A web application framework for your data.
    '''),

    dcc.Graph(
        id='example-graph',
        figure=fig
        )
    ])


if __name__ == '__main__':
    app.run_server(debug=True)

I get this error when trying to run the above code:

---------------------------------------------------------------------------
ImportError                               Traceback (most recent call last)
<ipython-input-36-a81edd5f2a5b> in <module>
     25 
     26 if __name__ == '__main__':
---> 27     app.run_server(debug=True)

~\AppData\Local\Continuum\anaconda3\lib\site-packages\dash\dash.py in run_server(self, port, debug, dev_tools_serve_dev_bundles, dev_tools_hot_reload, dev_tools_hot_reload_interval, dev_tools_hot_reload_watch_interval, dev_tools_hot_reload_max_retry, dev_tools_silence_routes_logging, **flask_run_options)
   1283                     )
   1284 
-> 1285                 return dict(
   1286                     user_callback_output=map_grouping(lambda x: no_update, output),
   1287                     interval_disabled=False,

~\AppData\Local\Continuum\anaconda3\lib\site-packages\flask\app.py in run(self, host, port, debug, load_dotenv, **options)
    938         cli.show_server_banner(self.env, self.debug, self.name, False)
    939 
--> 940         from werkzeug.serving import run_simple
    941 
    942         try:

~\AppData\Local\Continuum\anaconda3\lib\site-packages\werkzeug\serving.py in <module>
     26 
     27 from ._internal import _log
---> 28 from ._internal import _wsgi_encoding_dance
     29 from .exceptions import InternalServerError
     30 from .urls import uri_to_iri

ImportError: cannot import name '_wsgi_encoding_dance' from 'werkzeug._internal' (C:\Users\vmehta\AppData\Local\Continuum\anaconda3\lib\site-packages\werkzeug\_internal.py)

Answer 1

The error code is saying that it is trying to do relative import and it cannot find the file _wsgi_encoding_dance in the _internal folder within the site-packages/werkzeug package.

Check the package requirements and make sure to install the correct package dependency versions.