Thanks this was very helpful.
In the returned FIELDS array, for every field, there is also a TYPE label returned as part of the returned dict.
Looks like the following:
C = CHAR (or something that inherits it, like CUKY)
D = DATS
I = INTn
N = NUMC (or something that inherits it, like ACCP or QUAN)
P = DEC (or something that inherits it, like CURR)