None of the above worked for me. With Raspbian Stretch (June 2018 Version, Kernel 4.14), Python 3.5 and picamera 1.13 I used:

import picamera

with picamera.PiCamera() as cam:
    print(vars(cam))

NOTE: picamera 1.13 does have attribute cam.revision, but some other versions do not have given attribute. Safe approach is to print all attributes.

None of the above worked for me. With Raspbian Stretch (June 2018 Version, Kernel 4.14), Python 3.5 and picamera 1.13 I used:

import picamera

with picamera.PiCamera() as cam:
    print(cam.revision)

None of the above worked for me. With Raspbian Stretch (June 2018 Version, Kernel 4.14), Python 3.5 and picamera 1.13 I used:

import picamera

with picamera.PiCamera() as cam:
    print(cam.revision)

None of the above worked for me. With Raspbian Stretch (June 2018 Version, Kernel 4.14), Python 3.5 and picamera 1.13 I used:

import picamera

with picamera.PiCamera() as cam:
    print(vars(cam))

NOTE: picamera 1.13 does have attribute cam.revision, but some other versions do not have given attribute. Safe approach is to print all attributes.