WALL·E fail with report: "Названия заглавными буквами с подчёркиванием принято использовать только для глобальных переменных. (например, debug, testing, csrf_enabled, secret_key, sqlalchemy_database_uri, sqlalchemy_track_modifications, sqlalchemy_migrate_repo, debug, development, debug, development, debug, testing)"

valli_fail.py

import os
basedir = os.path.abspath(os.path.dirname(__file__))

DEBUG = False
DEVELOPMENT = False
TESTING = False
CSRF_ENABLED = False
SECRET_KEY = ''
SQLALCHEMY_DATABASE_URI = ''
SQLALCHEMY_TRACK_MODIFICATIONS = False
SQLALCHEMY_MIGRATE_REPO = ''


class Config(object):
    DEBUG = False
    TESTING = False
    CSRF_ENABLED = True
    SECRET_KEY = 'top  secret!'
    SQLALCHEMY_DATABASE_URI = os.environ['DATABASE_URL']
    SQLALCHEMY_TRACK_MODIFICATIONS = True
    SQLALCHEMY_MIGRATE_REPO = os.path.join(basedir, 'db_repository')


class ProductionConfig(Config):
    DEBUG = False


class StagingConfig(Config):
    DEVELOPMENT = True
    DEBUG = True


class DevelopmentConfig(Config):
    DEVELOPMENT = True
    DEBUG = True


class TestingConfig(Config):
    TESTING = True