code: def set_satchel_value(self, satchel, key, value):
          
          satchel = self.get_satchel(satchel)
          r = satchel.local_renderer
          setattr(r.env, key, value)
          print('Set %s=%s in satchel %s.' % (key, value, satchel.name))
docs: Sets a key/value pair in a satchel's local renderer.