我做错了什么,这两个循环不起作用？链接是一个列表.

links = ['newarklongtermparking.com',
 'www.airportparkingreservations.com',
 'airparkparking.com',
 'jfklongtermparking.com',
 'book2park.com',
 'globalairportparking.com',
 'neworleansparking.com',
 'parkwayparking.com',
 'www.airportparkinginc.com',
 'airportparkfly.com',
 'unitedairportparking.com',
 'www.way.com',
 'cheapairportparking.org',
 'wallypark.com',
 'parkbytheports.com',
 'www.cheapparkfly.com']

删除www.

for a in links:
    if (a[0] == a[1] == a[2] == 'w'):
        a = a[4:]

添加正确的链接形式

for a in links:
    a = 'https://www.' + a

如何默认选择图例中的一项，而取消选择其他项目？

我希望最初的情节看起来像这样：

#prepare thr chart
fig = px.line(df, x='date', y='diesel_price', color='region', 
                title='Diesel price in the US', 
                labels={'date':'Date', 
                'diesel_price':'Price ($)', 'region':'Region'})

app.layout = html.Div([
    html.H4('Metrics for trucking companies'),
    dcc.Graph(figure=fig),
])

if __name__ == '__main__':
    app.run_server(debug=True, host='0.0.0.0', port=8050)