Loads settings info from the settings json file

        :returns: True if the settings info is valid
        :rtype: boolean

def __load_settings_from_file(self):
        """
        Loads settings info from the settings json file

        :returns: True if the settings info is valid
        :rtype: boolean
        """
        filename = self.get_base_path() + 'settings.json'

        if not exists(filename):
            raise OneLogin_Saml2_Error(
                'Settings file not found: %s',
                OneLogin_Saml2_Error.SETTINGS_FILE_NOT_FOUND,
                filename
            )

        # In the php toolkit instead of being a json file it is a php file and
        # it is directly included
        with open(filename, 'r') as json_data:
            settings = json.loads(json_data.read())

        advanced_filename = self.get_base_path() + 'advanced_settings.json'
        if exists(advanced_filename):
            with open(advanced_filename, 'r') as json_data:
                settings.update(json.loads(json_data.read()))  # Merge settings

        return self.__load_settings_from_dict(settings)