can we append a values in binaryarray in python.? :     x=[12,23,36,48] 

    z=bytearray(x)

    z.append(13)

>>> 

    z
    bytearray(b'\x0c\x17$0\r').

I want to append a value in bytesarray. It's not given me error but not showing the required result. 
Please help me out. 