<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_class_from_settings_full_path(settings_key):
 """Get a class from it's full path. Example: some.path.module.MyClass """

    cls_path = getattr(settings, settings_key, None)

    if not cls_path:
        raise NotImplementedError()

    try:
        module_name, class_name = cls_path.rsplit('.', 1)
    except ValueError:
        raise ImproperlyConfigured("{0} must be of the form "
                                   "'some.path.module.MyClass'".format(
                                                                settings_key))

    manager_module = importlib.import_module(module_name)

    if not manager_module:
        raise ImproperlyConfigured("{0} refers to a module that has not been "
                                   "installed".format(settings_key))

    return getattr(manager_module, class_name)