[Traceback (most recent call last):
  File "./manage.py", line 22, in <module>
    execute_from_command_line(sys.argv)
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/management/__init__.py", line 367, in execute_from_command_line
    utility.execute()
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/management/__init__.py", line 359, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/management/base.py", line 294, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/management/base.py", line 345, in execute
    output = self.handle(*args, **options)
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/management/commands/dumpdata.py", line 200, in handle
    object_count=object_count,
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/serializers/__init__.py", line 129, in serialize
    s.serialize(queryset, **options)
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/serializers/base.py", line 79, in serialize
    for count, obj in enumerate(queryset, start=1):
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/core/management/commands/dumpdata.py", line 182, in get_objects
    for obj in queryset.iterator():
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/db/models/query.py", line 66, in __iter__
    obj = model_cls.from_db(db, init_list, row[model_fields_start:model_fields_end])
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/db/models/base.py", line 565, in from_db
    new = cls(*values)
  File "/home/ubuntu/.virtualenvs/djangodev/lib/python3.5/site-packages/django/db/models/base.py", line 481, in __init__
    setattr(self, field.attname, val)
AttributeError: can't set attribute