When starting Django project, report attributeerror: STR object has no attribute dcode‘

Wrong presentation ：

 File "/home/lhz/.virtualenvs/python37_django/lib/python3.7/site-packages/django/db/backends/mysql/operations.py", line 146, in last_executed_query
    query = query.dcode(errors='replace')

resolvent ：

Click on the last file directory , Automatically enter this file ：/home/lhz/.virtualenvs/python37_django/lib/python3.7/site-packages/django/db/backends/mysql/operations.py

# Will be the first 165 In a row decode Modified into encode,
if query is not None:
query = query.decode(errors='replace')
return query