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You can connect your Flask backend to Chrome DevTools using Subtrace with just one line of code. With Subtrace, you can inspect the status, headers, payload, and latency of all API requests so you can debug way faster. To begin with, install Subtrace: 
pip install subtrace
For this guide, we’ll use the following hello.py Flask app as an example: 
# Add this line to install Subtrace on your Flask server
import subtrace

from flask import Flask                                                                                             

app = Flask(__name__)
                         
@app.route("/")          
def hello_world():
    return "<p>Hello, World!</p>"
Before we move on to the next step, get a SUBTRACE_TOKEN from the Subtrace dashboard for free and set it as an environment variable. 
# get a tracer token for free at https://subtrace.dev/dashboard
export SUBTRACE_TOKEN=
Now use the flask command to start the server on port 5000: 
flask --app hello run
Send some requests to localhost:5000 to see them in Chrome DevTools in the Subtrace dashboard!