flask tumblelog is not working

[vikashruhil]

Vikashs-MacBook-Air:tumblelog vikashruhil$ python manage.py runserver
Traceback (most recent call last):
File "manage.py", line 6, in
from tumblelog import app
File "/Users/vikashruhil/Downloads/flask-tumblelog-master/tumblelog/init.py", line 18, in
register_blueprints(app)
File "/Users/vikashruhil/Downloads/flask-tumblelog-master/tumblelog/init.py", line 13, in register_blueprints
from tumblelog.views import posts
File "/Users/vikashruhil/Downloads/flask-tumblelog-master/tumblelog/views.py", line 5, in
from tumblelog.models import Post, Comment
File "/Users/vikashruhil/Downloads/flask-tumblelog-master/tumblelog/models.py", line 6, in
class Post(db.DynamicDocument):
File "/usr/local/lib/python2.7/site-packages/mongoengine/base/metaclasses.py", line 361, in new
meta['index_specs'] = new_class._build_index_specs(meta['indexes'])
File "/usr/local/lib/python2.7/site-packages/mongoengine/base/document.py", line 722, in _build_index_specs
unique_indices = cls._unique_with_indexes()
File "/usr/local/lib/python2.7/site-packages/mongoengine/base/document.py", line 861, in _unique_with_indexes
field.document_type != cls):
File "/usr/local/lib/python2.7/site-packages/mongoengine/fields.py", line 563, in document_type
self.document_type_obj = get_document(self.document_type_obj)
File "/usr/local/lib/python2.7/site-packages/mongoengine/base/common.py", line 25, in get_document
""".strip() % name)
mongoengine.errors.NotRegistered: Comment has not been registered in the document registry.
Importing the document class automatically registers it, has it
been imported?

[thinkerou]

Please move class Comment to class Post before. http://stackoverflow.com/questions/29434854/error-in-tumblelog-application-development-using-flask-and-mongoengine

[knaggita]

start with class comment followed by post(interchange their order)

[afizing]

I did that .. but unfortunately still getting the same error.