def create_comment(self, comment, repository_id, pull_request_id, thread_id, project=None):
        """CreateComment.
        [Preview API] Create a comment on a specific thread in a pull request (up to 500 comments can be created per thread).
        :param :class:`<Comment> <azure.devops.v5_1.git.models.Comment>` comment: The comment to create. Comments can be up to 150,000 characters.
        :param str repository_id: The repository ID of the pull request's target branch.
        :param int pull_request_id: ID of the pull request.
        :param int thread_id: ID of the thread that the desired comment is in.
        :param str project: Project ID or project name
        :rtype: :class:`<Comment> <azure.devops.v5_1.git.models.Comment>`
        """
        route_values = {}
        if project is not None:
            route_values['project'] = self._serialize.url('project', project, 'str')
        if repository_id is not None:
            route_values['repositoryId'] = self._serialize.url('repository_id', repository_id, 'str')
        if pull_request_id is not None:
            route_values['pullRequestId'] = self._serialize.url('pull_request_id', pull_request_id, 'int')
        if thread_id is not None:
            route_values['threadId'] = self._serialize.url('thread_id', thread_id, 'int')
        content = self._serialize.body(comment, 'Comment')
        response = self._send(http_method='POST',
                              location_id='965a3ec7-5ed8-455a-bdcb-835a5ea7fe7b',
                              version='5.1-preview.1',
                              route_values=route_values,
                              content=content)
        return self._deserialize('Comment', response)