django: change primary key - export data using django admin dumpdata, edit json file and load data again

change_pk_values_in_laoddata_json.py

import json
data = json.load(open('data.json'))

# get changed fields
# import model
model = User

changes = [(unicode(x.related_model._meta), x.field.name) for x in User._meta.get_all_related_objects()] # replace User with your model

m = {}
for u in model.objects.all():
  m[u.id] = str(u.uuid) # lookup key is your old field, value the new one

changes = dict(changes)
for idx, entry in enumerate(data):
  f = changes.get(entry['model'])
  if f is not None:
    old = entry['fields'][f] 
    new = m.get(old)
    print "Changed in model '%s' the field '%s' from %s to %s" % (entry['model'], f, repr(old), repr(new))
    data[idx]['fields'][f] = new
  if entry['model'] == unicode(model._meta):
    old = entry['pk']
    new = m.get(old)
    print "Changed pk in model '%s' from %s to %s" % (entry['model'], repr(old), repr(new))
    data[idx]['pk'] = new
    del data[idx]['fields']['uuid'] # change uuid to your soon-to-be pk field
    
json.dump(data, open('data_new.json', 'w'))