text: import os
  import dotenv
  dotenv.load()
  
  basedir = os.path.abspath(os.path.dirname(__file__))
  
  
  class Config:
      SECRET_KEY = os.environ.get('SECRET_KEY')
      SQLALCHEMY_COMMIT_ON_TEARDOWN = True
      SQLALCHEMY_TRACK_MODIFICATIONS = True
  
  
  class DevelopmentConfig(Config):
      DEBUG = True
      SQLALCHEMY_DATABASE_URI = os.environ.get('DEV_DATABASE_URL')
  
  
  class TestingConfig(Config):
      TESTING = True
      SQLALCHEMY_DATABASE_URI = os.environ.get('TEST_DATABASE_URL')
  
  
  class ProductionConfig(Config):
      SQLALCHEMY_DATABASE_URI = os.environ.get('DATABASE_URL')
  
  
  config = {
      'development': DevelopmentConfig,
      'testing': TestingConfig,
      'production': ProductionConfig,
      'default': DevelopmentConfig
  }
  