'Add comment to node
:param version_slug: Version slug to use for node lookup
:param page: Page to attach comment to
:param content_hash: Hash of content to apply comment to
:param commit: Commit that updated comment
:param user: :py:class:`User` instance that created comment
:param text: Comment text'

def add_comment(self, version_slug, page, content_hash, commit, user, text):

    from readthedocs.comments.models import DocumentNode
    try:
        node = self.nodes.from_hash(version_slug, page, content_hash)
    except DocumentNode.DoesNotExist:
        version = self.versions.get(slug=version_slug)
        node = self.nodes.create(version=version, page=page, hash=content_hash, commit=commit)
    return node.comments.create(user=user, text=text)
