code: def is53(msg):
      
  
      if allzeros(msg):
          return False
  
      d = hex2bin(data(msg))
  
      # status bit 1, 13, 24, 34, 47
  
      if wrongstatus(d, 1, 3, 12):
          return False
  
      if wrongstatus(d, 13, 14, 23):
          return False
  
      if wrongstatus(d, 24, 25, 33):
          return False
  
      if wrongstatus(d, 34, 35, 46):
          return False
  
      if wrongstatus(d, 47, 49, 56):
          return False
  
      ias = ias53(msg)
      if ias is not None and ias > 500:
          return False
  
      mach = mach53(msg)
      if mach is not None and mach > 1:
          return False
  
      tas = tas53(msg)
      if tas is not None and tas > 500:
          return False
  
      vr = vr53(msg)
      if vr is not None and abs(vr) > 8000:
          return False
  
      return True
docs: Check if a message is likely to be BDS code 5,3
      (Air-referenced state vector)
  
      Args:
          msg (String): 28 bytes hexadecimal message string
  
      Returns:
          bool: True or False