code: def expect_flow_sequence(self):
      self.write_indicator("[", True, whitespace=True)
      self.flow_level += 1
      self.increase_indent(flow=True)
      self.state = self.expect_first_flow_sequence_item
  
imports: from .error import YAMLError
  from .events import *
label_desc: Use image node_id 16 for calling the Emitter obj's underlying member method code with example usage: obj.expect_flow_sequence() without return types