Previously, if one attempted to set a JSONField on an instantiated but

unsaved model instance to an object or list literal

(e.g., mymodel.myfield = {'foo': 'bar'}) the field would attempt to

load the value as if it were a string with json.loads, which would

result in a TypeError.
We are now more deliberate when we call json.loads in post_init --

we only call it for string types. Otherwise, when we receive a value

that could be considered a deserialized JSON value (such as a dict,

list, int, or float), we know that these cannot come from the database

and are therefore being set on an unsaved instance. We then treat them

as deserialized values and do not modify them or attempt to load them.
In the case where we do not understand the type to be a deserialized

value, we still reset the value to an empty object.

Ran unit tests. Without this fix applied, the new unit test fails.