Flask (Python)

import os, requests
from flask import Flask, request, jsonify

app = Flask(__name__)

def is_disposable(email):
    try:
        r = requests.get(
            "https://api.disposableguard.com/v1/check",
            params={"email": email},
            headers={"Authorization": f"Bearer {os.environ['DG_KEY']}"},
            timeout=5,
        )
        if r.status_code == 200:
            return r.json()["is_disposable"]
    except requests.RequestException:
        pass
    return False

@app.route("/signup", methods=["POST"])
def signup():
    email = request.json.get("email")
    if is_disposable(email):
        return jsonify({"error": "Please use a real email address."}), 400
    # ...signup logic
    return jsonify({"ok": True})