How to tag users via Instagram Graph API - Python

Question

I am looking to tag users when I publish media via the Instagram Graph API.

I have been able to successfully publish photos and videos but have not been able to tag users.

This is what I am trying:

params = getCreds()  # get creds from defines
params['media_type'] = 'IMAGE'  # type of asset
params['media_url'] = 'path to my image'  # url 
params['caption'] = 'My Caption'
params['user_tags'] = ('kevinhart4real',0.5, 0.8)
imageMediaObjectResponse = createMediaObject(params)  # create a media object

Where the person I want to tag is Kevinhart4real and I want to place the tag at the XY coordinates of (.5,.8)

I have been following this tutorial