code: def is17(msg):
      
  
      if allzeros(msg):
          return False
  
      d = hex2bin(data(msg))
  
      if bin2int(d[28:56]) != 0:
          return False
  
      caps = cap17(msg)
  
      # basic BDS codes for ADS-B shall be supported
      #   assuming ADS-B out is installed (2017EU/2020US mandate)
      # if not set(['BDS05', 'BDS06', 'BDS08', 'BDS09', 'BDS20']).issubset(caps):
      #     return False
  
      # at least you can respond who you are
      if 'BDS20' not in caps:
          return False
  
      return True
docs: Check if a message is likely to be BDS code 1,7
  
      Args:
          msg (String): 28 bytes hexadecimal message string
  
      Returns:
          bool: True or False