old_contents: # -*- coding: utf-8 -*-
  """ Default configuration for the application
  
  This data must be supplemented with custom configuration to which
  URL_SHORTENER_CONFIGURATION environment variable points, overriding
  some of the values specified here.
  
  :var SQLALCHEMY_DATABASE_URI: uri of database to be used by the application.
  
  The default value serves only as documentation, and it was taken from:
  http://docs.sqlalchemy.org/en/latest/core/engines.html#database-urls
  
  :var MIN_NEW_ALIAS_LENGTH: a minimum number of characters in a newly
  generated alias
  :var MAX_NEW_ALIAS_LENGTH: a maximum number of characters in a newly
  generated alias
  :var SECRET_KEY: a secret key to be used by the application
  :var LOG_FILE: a name of file to which the application writes logs.
  The value can be None, in which case the application won't write logs
  to any file.
  
  If the value is set, it must consist of an existing directory (if any),
  but the file doesn't have to exist. The application uses timed roating
  file handler with interval of one day, so the file specified here will
  be created (if it doesn't exist yet) and used for one day. After that,
  it will be renamed, and another file with the same name will be created
  in the same directory and used.
  
  :var INTEGRITY_ERROR_LIMIT: a maximum number of integrity errors allowed to
  occur when handling a request for a shortened URL, before logging a warning
  
  :var GOOGLE_SAFE_BROWSING_API_KEY: a value necessary for querying
  Google Safe Browsing API.
  :var HOST_BLACKLIST_FILE: a name of file storing blacklisted hosts
  (hostnames and ip addresses). The value must be either None, or
  a name of an existing file containing blacklisted hosts in
  a sorted order.
  
  If the value is None, no host blacklist file will be used.
  
  :var RECAPTCHA_PUBLIC_KEY: a value used as a public key for reCAPTCHA,
  provided by Google: https://developers.google.com/recaptcha/docs/start
  
  :var RECAPTCHA_PRIVATE_KEY: a value used as a private key for reCAPTCHA,
  provided by Google: https://developers.google.com/recaptcha/docs/start
  
  :var ADMIN_EMAIL: email address of administrator(s) of the service provided
  by an installation of this application
  
  :var BLACKLISTED_HOSTS: a custom list of strings representing blacklisted
  hosts
  
  :var WHITELISTED_HOSTS: a custom list of strings representing whitelisted
  hosts. URLs with them will not be tested against blacklist.
  """
  SQLALCHEMY_DATABASE_URI = (
      'dialect+driver://username:password@host:port/database'
  )
  MIN_NEW_ALIAS_LENGTH = 1
  MAX_NEW_ALIAS_LENGTH = 4
  SECRET_KEY = 'a secret key'
  LOG_FILE = None
  INTEGRITY_ERROR_LIMIT = 10
  GOOGLE_SAFE_BROWSING_API_KEY = 'a key'
  HOST_BLACKLIST_FILE = None
  RECAPTCHA_PUBLIC_KEY = 'public-recaptcha-key'
  RECAPTCHA_PRIVATE_KEY = 'private-recaptcha-key'
  ADMIN_EMAIL = 'admin@your-domain.com'
  BLACKLISTED_HOSTS = []
  WHITELISTED_HOSTS = []
  
new_contents: # -*- coding: utf-8 -*-
  """ Default configuration for the application
  
  This data must be supplemented with custom configuration to which
  URL_SHORTENER_CONFIGURATION environment variable points, overriding
  some of the values specified here.
  
  :var SQLALCHEMY_DATABASE_URI: uri of database to be used by the application.
  
  The default value serves only as documentation, and it was taken from:
  http://docs.sqlalchemy.org/en/latest/core/engines.html#database-urls
  
  :var MIN_NEW_ALIAS_LENGTH: a minimum number of characters in a newly
  generated alias
  :var MAX_NEW_ALIAS_LENGTH: a maximum number of characters in a newly
  generated alias
  :var SECRET_KEY: a secret key to be used by the application
  :var LOG_FILE: a name of file to which the application writes logs.
  The value can be None, in which case the application won't write logs
  to any file.
  
  If the value is set, it must consist of an existing directory (if any),
  but the file doesn't have to exist. The application uses timed roating
  file handler with interval of one day, so the file specified here will
  be created (if it doesn't exist yet) and used for one day. After that,
  it will be renamed, and another file with the same name will be created
  in the same directory and used.
  
  :var INTEGRITY_ERROR_LIMIT: a maximum number of integrity errors allowed to
  occur when handling a request for a shortened URL, before logging a warning
  
  :var GOOGLE_SAFE_BROWSING_API_KEY: a value necessary for querying
  Google Safe Browsing API.
  
  :var RECAPTCHA_PUBLIC_KEY: a value used as a public key for reCAPTCHA,
  provided by Google: https://developers.google.com/recaptcha/docs/start
  
  :var RECAPTCHA_PRIVATE_KEY: a value used as a private key for reCAPTCHA,
  provided by Google: https://developers.google.com/recaptcha/docs/start
  
  :var ADMIN_EMAIL: email address of administrator(s) of the service provided
  by an installation of this application
  
  :var BLACKLISTED_HOSTS: a custom list of strings representing blacklisted
  hosts
  
  :var WHITELISTED_HOSTS: a custom list of strings representing whitelisted
  hosts. URLs with them will not be tested against blacklist.
  """
  SQLALCHEMY_DATABASE_URI = (
      'dialect+driver://username:password@host:port/database'
  )
  MIN_NEW_ALIAS_LENGTH = 1
  MAX_NEW_ALIAS_LENGTH = 4
  SECRET_KEY = 'a secret key'
  LOG_FILE = None
  INTEGRITY_ERROR_LIMIT = 10
  GOOGLE_SAFE_BROWSING_API_KEY = 'a key'
  RECAPTCHA_PUBLIC_KEY = 'public-recaptcha-key'
  RECAPTCHA_PRIVATE_KEY = 'private-recaptcha-key'
  ADMIN_EMAIL = 'admin@your-domain.com'
  BLACKLISTED_HOSTS = []
  WHITELISTED_HOSTS = []
  
subject: Remove HOST_BLACKLIST_FILE configuration option