code: def verbose(self):
          
          try:
              before = self.git.show('HEAD~1:content').strip()
          except sh.ErrorReturnCode_128:
              before = None
          after = self.git.show('HEAD:content').strip()
          if before is not None:
              return (u'{subject}\nNew value:\n{after}\n'
                      u'Old value:\n{before}\n'
                      .format(subject=self.subject,
                              before=before,
                              after=after))
          else:
              return u'\n'.join([self.subject, after])
docs: Return changes in human-friendly format #14