def retrieve(key, path):
epub = Epub()
epub.expand(path)
space = Space(epub)
line_order = LineOrder(key, len(space))
def read_int(bit_size):
bit_buffer = ''
for i in range(bit_size):
if space[line_order.next()]:
bit_buffer += '1'
else:
bit_buffer += '0'
return int(bit_buffer, 2)
header_size = read_int(HEADER_BIT_SIZE)
message_size = read_int(header_size)
message = ''
for i in range(0, message_size, CHAR_BIT_SIZE):
message += chr(read_int(CHAR_BIT_SIZE))
epub.cleanup()
return message
