rpc exports functions

hi, in your python script. rpc exports is used like this.
rpc.exports = {
      enumerateRanges: function (prot) {
        return Process.enumerateRangesSync(prot);
      },
agent = script.exports
ranges = agent.enumerate_ranges(PERMS)
why it is called by the name  enumerate_ranges instead of  enumerateRanges?