code: def set_ext_param(self, ext_key, param_key, val):
          '''
          Set the provided parameter in a set of extension parameters.
          '''
          if not self.extensions[ext_key]:
              self.extensions[ext_key] = defaultdict(lambda: None)
          self.extensions[ext_key][param_key] = vaf set_ext_param(self, ext_key, param_key, val):
          '''
          Set the provided parameter in a set of extension parameters.
          '''
          if not self.extensions[ext_key]:
              self.extensions[ext_key] = defaultdict(lambda: None)
          self.extensions[ext_key][param_key] = val
docs: Set the provided parameter in a set of extension parameters.