code: def check_simple_key(self):
      length = 0
      if (
          isinstance(self.event, NodeEvent)
          and self.event.anchor is not None
      ):
          if self.prepared_anchor is None:
              self.prepared_anchor = self.prepare_anchor(
                  self.event.anchor
              )
          length += len(self.prepared_anchor)
      if (
          isinstance(self.event, (ScalarEvent, CollectionStartEvent))
          and self.event.tag is not None
      ):
          if self.prepared_tag is None:
              self.prepared_tag = self.prepare_tag(self.event.tag)
          length += len(self.prepared_tag)
      if isinstance(self.event, ScalarEvent):
          if self.analysis is None:
              self.analysis = self.analyze_scalar(self.event.value)
          length += len(self.analysis.scalar)
      return length < 128 and (
          isinstance(self.event, AliasEvent)
          or (
              isinstance(self.event, ScalarEvent)
              and not self.analysis.empty
              and not self.analysis.multiline
          )
          or self.check_empty_sequence()
          or self.check_empty_mapping()
      )
  
imports: from .error import YAMLError
  from .events import *
label_desc: Use image node_id 35 for calling the Emitter obj's underlying member method code with example usage: obj.check_simple_key() and returns: unknown