def ahead(self):
        if self.merge_refspec:
            return len(self.repo.shell('git', 'log', '--no-merges', '--pretty=format:%H', (self.repo.master, self.refspec) % '%s..%s').split)
        return None
dataset/ETHPy150Open nowells/git-goggles/gitgoggles/git.py/Branch.ahead/swapped operands of `%`