Parsing indexed key pairs from a QueryDict in Django or Python
I think it's the wrong way. To make it easier, you should set the traditional argument to true in $.param(). 
This is the difference between traditional is true and false:
var obj = { a: [ 1, 2, 3 ] };
$.param(myObject); // a%5B%5D=1&a%5B%5D=2&a%5B%5D=3 ==> a[]=1&a[]=2&a[]=3
$.param(myObject, true); // b=1&b=2&b=3

With traditional is true, you can use this code in your Django project:
request.POST.getlist('a[]') # [1, 2, 3]
From a jQuery form, I get the following QueryDict, when I submit a form:
<QueryDict: {'marc[0].sub': [''], 'csrfmiddlewaretoken': ['K6Fd4AbFP2bLmAWaD4hAGoFbzyKjHErN'], 'field': [''], 'marc[2].field': ['856'], 'marc[0].field': ['001'], 'sub': [''], 'marc[1].sub': ['a'], 'marc[2].sub': ['u'], 'marc[1].field': ['655']}>
I can get at the data that I want if I use the very specific call in my view.  For example:
print(QueryDict.getlist(request.POST, 'marc[2].sub'))
...shows the desired 'u' on the console, but I'm not sure how to loop through indexed key pairs in this odd format, where the keys have no relation, except the interloping index number.   Eventually, I need a for each type statement, where I'd loop through the following:
marc[0].field: 001 and marc[0].sub: ''
marc[1].field: 655 and marc[1].sub: 'a'
marc[2].field: 856 and marc[2].sbu: 'u'
...or, better, would be to loop through something more like this:
field_subs = ('001', ''), ('655', 'a'), ('856', 'u')
...to perform another operation.
e.g.
for field_sub in field_subs:
If I need to submit more code, am heading at this the wrong way, or making it more difficult than it is, I'd appreciate any direction.  I'm using Django 1.9
Thanks