old_contents: from os import getenv
  
  class Config(object):
      DEBUG = False
      TESTING = False
      API_KEY = getenv('API_KEY')
      SQLALCHEMY_DATABASE_URI = getenv('DATABASE_URL')
      MAILGUN_API_URL = "https://api.mailgun.net/v2"
      MAILGUN_API_KEY = getenv('MAILGUN_API_KEY')
      LOCAL_PART_HASH_LENGTH = 8
  
  class ProductionConfig(Config):
      DEBUG = False
      TESTING = False
  
  class DevelopmentConfig(Config):
      DEBUG = True
      SQLALCHEMY_DATABASE_URI = 'sqlite:///app.db'
  
  class TestingConfig(Config):
      TESTING = True
  
new_contents: from os import getenv
  
  class Config(object):
      DEBUG = False
      TESTING = False
      API_KEY = getenv('API_KEY')
      SQLALCHEMY_DATABASE_URI = getenv('DATABASE_URL').replace('mysql2:', 'mysql:')
      MAILGUN_API_URL = "https://api.mailgun.net/v2"
      MAILGUN_API_KEY = getenv('MAILGUN_API_KEY')
      LOCAL_PART_HASH_LENGTH = 8
  
  class ProductionConfig(Config):
      DEBUG = False
      TESTING = False
  
  class DevelopmentConfig(Config):
      DEBUG = True
      SQLALCHEMY_DATABASE_URI = 'sqlite:///app.db'
  
  class TestingConfig(Config):
      TESTING = True
  
subject: Support mysql2: database url's