I have a Python script that contains a plain text password used to bind Mac to AD.
I need to deploy this script to few Macs.
How can I secure password which is in plain text, so that no one can see the password?
I don't want to use base64, I'd need something stronger than base64.
Try storing the password in a variable in a separate Python script. 
pass.py
password = 'PASSWORD'
Import the variable from this script separately.
main.py
from pass import password
This will create a bytecode file named pass.pyc. Now you can delete pass.py and continue using pass.pyc, which isn't human-readable and much harder to decompile.
Edit: If somebody has access to your source code, they can still see the password with a print statement!
Edit 2: As Giacomo Alzetta commented, the password is still human-readable here, but it comes down to the "attack model" here. If someone really wants to, they can still dig around and find it. Other alternatives are encryption algorithms available in OpenSSL. Symmetric key algorithms might still not be useful for you since you'd probably have to store the encryption key within the source code. Asymmetric key algorithms might work.
How to secure plain text Password in python script