'Create a review comment on this pull request.
All parameters are required by the GitHub API.
:param str body: The comment text itself
:param str commit_id: The SHA of the commit to comment on
:param str path: The relative path of the file to comment on
:param int position: The line index in the diff to comment on.
:returns: The created review comment.
:rtype: :class:`~github3.pulls.ReviewComment`'

@requires_auth
def create_review_comment(self, body, commit_id, path, position):

    url = self._build_url(u'comments', base_url=self._api)
    data = {u'body': body, u'commit_id': commit_id, u'path': path, u'position': int(position)}
    json = self._json(self._post(url, data=data), 201)
    return self._instance_or_null(ReviewComment, json)
