code: def parse_flow_sequence_entry_mapping_key(self):
      token = self.get_token()
      if not self.check_token(
          ValueToken, FlowEntryToken, FlowSequenceEndToken
      ):
          self.states.append(
              self.parse_flow_sequence_entry_mapping_value
          )
          return self.parse_flow_node()
      else:
          self.state = self.parse_flow_sequence_entry_mapping_value
          return self.process_empty_scalar(token.end_mark)
  
imports: from .error import MarkedYAMLError
  from .tokens import *
  from .events import *
  from .scanner import *
label_desc: Use image node_id 24 for calling the Parser obj's underlying member method code with example usage: obj.parse_flow_sequence_entry_mapping_key() and returns: self, self