old_contents: SECRET_KEY = {'value':'{{ secret_key }}'}
  
  DEBUG = {'value':True}
  
  ALLOWED_HOSTS = {'default':[]}
  
  DATABASES = {'value':{}, 'update_dict':True}
  
new_contents: """This module defines the settings to be altered and how to handle them.
  
  Each setting should contain a dict with the following keys:
      'value': The content to be placed in `local_settings.py`
      'default': The content will be set as the default value in `settings.py`
          `<SETTING_NAME> = getattr(local_settings, <SETTING_NAME>, <default>)`
      'update_dict': If `True`, the value in `settings.py` will be updated with
          the one in `local_settings.py`.  Useful for things like DATABASES so the
          default setup can be left alone until modification is needed.
          Note that a 'value' must be present, even if it is an empty dict.
          `<SETTING_NAME>.update(getattr(local_settings, <SETTING_NAME>))`
  """
  SECRET_KEY = {'value':'{{ secret_key }}'}
  
  DEBUG = {'value':True}
  
  ALLOWED_HOSTS = {'default':[]}
  
  DATABASES = {'value':{}, 'update_dict':True}
  
subject: Add documentation to safe_settings.py