def ascii85Decode(stream):
 n = b = 0
 decodedStream = ''
 try:
  for c in stream:
   if (('!' <= c) and (c <= 'u')):
    n += 1
    b = ((b * 85) + (ord(c) - 33))
    if (n == 5):
     decodedStream += struct.pack('>L', b)
     n = b = 0
   elif (c == 'z'):
    assert (n == 0)
    decodedStream += '\x00\x00\x00\x00'
   elif (c == '~'):
    if n:
     for _ in range((5 - n)):
      b = ((b * 85) + 84)
     decodedStream += struct.pack('>L', b)[:(n - 1)]
    break
 except:
  return ((-1), 'Unspecified error')
 return (0, decodedStream)

def ascii85Decode ( stream ) : n = b = 0 decodedStream = '' try : for c in stream : if ( ( '!' <= c ) and ( c <= 'u' ) ) : n += 1 b = ( ( b * 85 ) + ( ord ( c ) - 33 ) ) if ( n == 5 ) : decodedStream += struct . pack ( '>L' , b ) n = b = 0 elif ( c == 'z' ) : assert ( n == 0 ) decodedStream += '\x00\x00\x00\x00' elif ( c == '~' ) : if n : for _ in range ( ( 5 - n ) ) : b = ( ( b * 85 ) + 84 ) decodedStream += struct . pack ( '>L' , b ) [ : ( n - 1 ) ] break except : return ( ( - 1 ) , 'Unspecified error' ) return ( 0 , decodedStream )
method to decode streams using ascii85 .