>>> b = bytearray(b'hello world!')
>>> b
bytearray(b'hello world!')
>>> b[0]
104
>>> b[0] = b'h'
Traceback (most recent call last):
File "", line 1, in
b[0] = b'h'
TypeError: an integer is required
>>> b[0] = 105
>>> b
bytearray(b'iello world!')
>>> for i in range(len(b)):
... b[i] += i
...
>>> b
bytearray(b'ifnos%}vzun,')