Update Definition not modifying service?

[RichardHughes2]

Using the Rest API Update Definition request I am attempting to update the domain values for a hosted layer in AGOL.  The requests returns a success, but the data is not updated in AGOL.  

There are not error messages or any issues that I can find.

Has anyone else had this problem when trying to update domains using the Update Definition?

There are views associated with this service, do those prevent using this Update Definition to modify the domains?

[RichardHughes2]

What I've found is that python None, True, and False values are automatically substituted for the null, true, and false values returned by the service definition.  Before submitting the post data I have to dump the data to a json string, then replace these python types with the associated json type.  Both are specified as strings since I am replacing the text in the json string.  

Other cleanup needed is to remove all single apostrophes from domain descriptions.