int32 scene_type 
float64 timestamp  
#0:TRAFFIC_LIGHT 1:RED ALERT 2:GREEN ADVICE 3.intersection collision warning 4:Left turn assistant 
# 5:Hazardous location warning 6:Speed limit warning 7:Vulnerable road user collision warning 8:Speed limit cancel 9:alert cancel
float64 guide_speed
TrafficLightInfo light_info
ParticipantInfo participant_info