Multi process error, When run the example 3 of Dash Tutorial Part 5

Dash Python
1 
import json
import os
import copy
import time
import datetime
import dash
from dash import dcc
from dash import html
from dash.dependencies import Input, Output, State
import plotly.express as px
import pandas as pd
import numpy as np
from flask_caching import Cache

external_stylesheets = [
    # Dash CSS
    'https://codepen.io/chriddyp/pen/bWLwgP.css',
    # Loading screen CSS
    'https://codepen.io/chriddyp/pen/brPBPO.css']

app = dash.Dash(__name__, external_stylesheets=external_stylesheets)
server = app.server

CACHE_CONFIG = {
    "CACHE_TYPE": "FileSystemCache",  # Flask-Caching related configs
    'CACHE_DIR': 'cache'
}
cache = Cache()
cache.init_app(app.server, config=CACHE_CONFIG)

N = 100

df = pd.DataFrame({
    'category': (
        (['apples'] * 5 * N) +
        (['oranges'] * 10 * N) +
        (['figs'] * 20 * N) +
        (['pineapples'] * 15 * N)
    )
})
df['x'] = np.random.randn(len(df['category']))
df['y'] = np.random.randn(len(df['category']))

app.layout = html.Div([
    dcc.Dropdown(
        id='dropdown',
        options=[{'label': i, 'value': i} for i in df['category'].unique()],
        value='apples'
    ),
    html.Div([
        html.Div(dcc.Graph(id='graph-1'), className="six columns"),
        html.Div(dcc.Graph(id='graph-2'), className="six columns"),
    ], className="row"),
    html.Div([
        html.Div(dcc.Graph(id='graph-3'), className="six columns"),
        html.Div(dcc.Graph(id='graph-4'), className="six columns"),
    ], className="row"),

    # signal value to trigger callbacks
    dcc.Store(id='signal')
])


# perform expensive computations in this "global store"
# these computations are cached in a globally available
# redis memory store which is available across processes
# and for all time.
@cache.memoize()
def global_store(value):
    # simulate expensive query
    print('Computing value with {}'.format(value))
    time.sleep(5)
    return df[df['category'] == value]


def generate_figure(value, figure):
    fig = copy.deepcopy(figure)
    filtered_dataframe = global_store(value)
    fig['data'][0]['x'] = filtered_dataframe['x']
    fig['data'][0]['y'] = filtered_dataframe['y']
    fig['layout'] = {'margin': {'l': 20, 'r': 10, 'b': 20, 't': 10}}
    return fig


@app.callback(Output('signal', 'data'), Input('dropdown', 'value'))
def compute_value(value):
    # compute value and send a signal when done
    global_store(value)
    return value


@app.callback(Output('graph-1', 'figure'), Input('signal', 'data'))
def update_graph_1(value):
    # generate_figure gets data from `global_store`.
    # the data in `global_store` has already been computed
    # by the `compute_value` callback and the result is stored
    # in the global redis cached
    return generate_figure(value, {
        'data': [{
            'type': 'scatter',
            'mode': 'markers',
            'marker': {
                'opacity': 0.5,
                'size': 14,
                'line': {'border': 'thin darkgrey solid'}
            }
        }]
    })


@app.callback(Output('graph-2', 'figure'), Input('signal', 'data'))
def update_graph_2(value):
    return generate_figure(value, {
        'data': [{
            'type': 'scatter',
            'mode': 'lines',
            'line': {'shape': 'spline', 'width': 0.5},
        }]
    })


@app.callback(Output('graph-3', 'figure'), Input('signal', 'data'))
def update_graph_3(value):
    return generate_figure(value, {
        'data': [{
            'type': 'histogram2d',
        }]
    })


@app.callback(Output('graph-4', 'figure'), Input('signal', 'data'))
def update_graph_4(value):
    return generate_figure(value, {
        'data': [{
            'type': 'histogram2dcontour',
        }]
    })


if __name__ == '__main__':
    app.run_server(debug=True,processes=6)

error:

Traceback (most recent call last):
  File "C:\Users\63036\Anaconda3\envs\yuketang\lib\threading.py", line 973, in _bootstrap_inner
    self.run()
  File "C:\Users\63036\Anaconda3\envs\yuketang\lib\threading.py", line 910, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\63036\Anaconda3\envs\yuketang\lib\site-packages\werkzeug\serving.py", line 948, in inner
    srv = make_server(
  File "C:\Users\63036\Anaconda3\envs\yuketang\lib\site-packages\werkzeug\serving.py", line 778, in make_server
    raise ValueError("cannot have a multithreaded and multi process server.")
ValueError: cannot have a multithreaded and multi process server.

win10
dash 2.0.0
dash-core-components 2.0.0
dash-html-components 2.0.0
dash-table 5.0.0
debugpy 1.4.3
decorator 5.1.0
defusedxml 0.7.1
entrypoints 0.3
Flask 2.0.1
Flask-Caching 1.10.1
Flask-Compress 1.10.1