def SequenceStart(self, event, loader):
    self._HandleAnchor(event)
    token, parent = self._top


    if token == _TOKEN_KEY:
      token, parent = self._stack[-2]
    sequence = self._builder.BuildSequence(parent)
    self._HandleValue(sequence)
    self._Push(_TOKEN_SEQUENCE, sequence)
Start of sequence scope
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/api/yaml_builder.py/BuilderHandler.SequenceStart