strip_tags.py

In [38]: from django.utils.html import strip_tags

In [39]: strip_tags(None)
Out[39]: u'None'

In [40]: post = {'brief': None}

In [41]: strip_tags(post.get('brief', ''))
Out[41]: u'None'

In [42]: strip_tags(post.get('brief') or '')
Out[42]: u''