Flask - add jinja2 extension

jinja2.exceptions.TemplateSyntaxError: Encountered unknown tag ‘break‘

To use {% break %} and {% continue %}, you need to add the following jinja2 extension:

app.jinja_env.add_extension(‘jinja2.ext.loopcontrols‘)

原文：https://www.cnblogs.com/zhangzhihui/p/12936310.html