<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def build_userlist(self, userlist_node):
 """parse `userlist` sections, and return a config.Userlist"""

        proxy_name = userlist_node.userlist_header.proxy_name.text
        config_block_lines = self.__build_config_block(
            userlist_node.config_block)
        return config.Userlist(
            name=proxy_name,
            config_block=config_block_lines)