Flask learning record 000: error summary

error 1：

ValueError: urls must start with a leading slash

The wrong meaning is ：url Must be “/ ” start

Because of my carelessness , Forget to write under a subdomain “/” Cause error ：

@app.route(“del”)

Due to less writing “/ ” Cause the above error , Should be changed to ：

@app.route(“/del”) 

error 2

<