Reformat; fix CI

.drone.yml

@@ -43,7 +43,7 @@ steps:
   image: node:10
   commands:
       - cd front
-      - npm install
+      - yarn
       - npm run lint
       - npm run build
 

app.py

@@ -4,7 +4,17 @@ import os
 import subprocess
 from logging.handlers import RotatingFileHandler
 from flask_babelex import gettext, Babel
-from flask import Flask, render_template, g, send_from_directory, jsonify, safe_join, request, flash, Response, Blueprint
+from flask import (
+    Flask,
+    render_template,
+    g,
+    send_from_directory,
+    jsonify,
+    safe_join,
+    request,
+    flash,
+    Response,
+)
 from flask_bootstrap import Bootstrap
 from flask_mail import Mail
 from flask_migrate import Migrate