在Buildbot中，是否可以让被触发的构建器向父构建器返回值？

from buildbot.plugins import util

# 父构建器
f = util.BuildFactory()
f.addStep(util.Trigger(schedulerNames=["child_scheduler"], waitForFinish=True))
f.addStep(util.SetPropertyFromCommand(command=["echo", "Parent build"], property="result"))

# 子构建器
c = util.BuildFactory()
c.addStep(util.ShellCommand(command=["echo", "Child build"]))
c.addStep(util.SetPropertyFromCommand(command=["echo", "Child build result"], property="result"))

# 配置构建器
c['properties'] = {'result': 'child_result'}
f['properties'] = {'result': util.Property('child_result')}

# 配置触发器
t = util.Triggerable(name="child_scheduler")
t.setBuilderNames(["child_builder"])

# 添加构建器和触发器到Buildbot配置
c['builders'] = [util.BuilderConfig(name="child_builder", factory=c)]
f['builders'] = [util.BuilderConfig(name="parent_builder", factory=f)]
c['schedulers'] = [t]

# 返回父构建器的结果
f.addStep(util.SetPropertyFromCommand(command=["echo", util.Property('child_result')], property="result"))

# 配置Buildbot
c['schedulers'] = [t]
c['builders'] = [util.BuilderConfig(name="child_builder", factory=c)]
f['builders'] = [util.BuilderConfig(name="parent_builder", factory=f)]