To transform a unicode string to a byte string in Python do this:

>>> 'foo'.encode('utf_8')
b'foo'

To transform a byte string to a unicode string:

>>> b'foo'.decode('utf_8')
'foo'

  1. To convert a string to bytes.

    data = ""               #string
data = "".encode()      #bytes
data = b""              #bytes

  2. To convert bytes to a String.

    data = b""              #bytes
data = b"".decode()     #string
data = str(b"")         #string

str to hex:

import codecs
hexlify = codecs.getencoder('hex')
hexlify(b'Blaah')[0]

out:

b'426c616168'

hex to str:

import codecs
decode_hex = codecs.getdecoder("hex_codec")
s = decode_hex(b'426c616168')[0]

out:

b'Blaah'

https://docs.python.org/3/library/winreg.html#
https://stackoverflow.com/questions/15128225/python-script-to-read-and-write-a-path-to-registry

import winreg

REG_PATH = r"Control Panel\Mouse"

def set_reg(name, value):
    try:
        winreg.CreateKey(winreg.HKEY_CURRENT_USER, REG_PATH)
        registry_key = winreg.OpenKey(winreg.HKEY_CURRENT_USER, REG_PATH, 0, 
                                       winreg.KEY_WRITE)
        winreg.SetValueEx(registry_key, name, 0, winreg.REG_SZ, value)
        winreg.CloseKey(registry_key)
        return True
    except WindowsError:
        return False

def get_reg(name):
    try:
        registry_key = winreg.OpenKey(winreg.HKEY_CURRENT_USER, REG_PATH, 0,
                                       winreg.KEY_READ)
        value, regtype = winreg.QueryValueEx(registry_key, name)
        winreg.CloseKey(registry_key)
        return value
    except WindowsError:
        return None

#Example MouseSensitivity
#Read value 
print (get_reg('MouseSensitivity'))

#Set Value 1/20 (will just write the value to reg, the changed mouse val requires a win re-log to apply*)
set_reg('MouseSensitivity', str(10))

#*For instant apply of SystemParameters like the mouse speed on-write, you can use win32gui/SPI
#http://docs.activestate.com/activepython/3.4/pywin32/win32gui__SystemParametersInfo_meth.html