No module named ‘haystack. Various Django error reporting solutions such as URLs

Report errors ：ModuleNotFoundError: No module named ‘haystack.urls’
solve ：

pip uninstall haystack
pip install django-haystack

Report errors ：cannot import name ‘smart_text’ from ‘django.utils.encoding’
solve ：setting.py Add

import django
from django.utils.encoding import smart_str
django.utils.encoding.smart_text = smart_str

Report errors ：ModuleNotFoundError: No module named ‘haystack.backends.whoosh_cn_backend’

solve ：setting.py Revision in China

'ENGINE': 'haystack.backends.whoosh_cn_backend.WhooshEngine',

by ：

 'ENGINE': 'haystack.backends.whoosh_backend.WhooshEngine',

Report errors ： cannot import name ‘url’ from ‘django.conf.urls’
solve ：

pip install Whoosh

modify ：

from django.conf.urls import url

by ：

from django.urls import re_path as url

Report errors ：django.db.utils.OperationalError: (1045, “Access denied for user ‘root’@‘localhost’ (using password: YES)”)

This is a mysql The password is wrong , Change to the correct password at the corresponding location ：

Report errors ：installing mysqlclient error: mysqlclient 1.4.0 or newer is required; you have 0.9.3
solve ：

pip3 uninstall mysqlclient
pip3 uninstall pymysql
pip3 install mysqlclient
pip3 install pymysql