def create_ca_file(anchor_list, filename):
 try:
  f = open(filename, 'w')
  for a in anchor_list:
   s = a.output(fmt='PEM')
   f.write(s)
  f.close()
 except:
  return None
 return filename

def create_ca_file ( anchor_list , filename ) : try : f = open ( filename , 'w' ) for a in anchor_list : s = a . output ( fmt = 'PEM' ) f . write ( s ) f . close ( ) except : return None return filename
concatenate all the certificates in anchor_list and write the result to file filename .