List merge requests that will close the issue when merged.

        Args:
            **kwargs: Extra options to send to the server (e.g. sudo)

        Raises:
            GitlabAuthenticationError: If authentication is not correct
            GitlabGetErrot: If the merge requests could not be retrieved

        Returns:
            list: The list of merge requests.

def closed_by(self, **kwargs):
        """List merge requests that will close the issue when merged.

        Args:
            **kwargs: Extra options to send to the server (e.g. sudo)

        Raises:
            GitlabAuthenticationError: If authentication is not correct
            GitlabGetErrot: If the merge requests could not be retrieved

        Returns:
            list: The list of merge requests.
        """
        path = '%s/%s/closed_by' % (self.manager.path, self.get_id())
        return self.manager.gitlab.http_get(path, **kwargs)