Retrieves the value of `key` from configuration in the following order:

    - from the session; if not found there then
    - from cookies; if not found there then
    - from the settings file if `search_in_settings` is True,
      otherwise this step is skipped; if not found there
    - `default` is returned

def get_config_value(request, key, default, search_in_settings=True):
    """Retrieves the value of `key` from configuration in the following order:

    - from the session; if not found there then
    - from cookies; if not found there then
    - from the settings file if `search_in_settings` is True,
      otherwise this step is skipped; if not found there
    - `default` is returned
    """
    value = request.session.get(key, request.COOKIES.get(key))

    if value is None:
        if search_in_settings:
            value = getattr(settings, key, default)
        else:
            value = default

    if isinstance(default, int):
        try:
            value = int(value)
        except ValueError:
            value = request.session[key] = int(default)

    return value