def _set_best(self, v, load=False):
    """
    Setter method for best, mapped from YANG variable /routing_system/route_map/content/match/additional_paths/advertise_set/best (uint32)
    If this variable is read-only (config: false) in the
    source YANG file, then _set_best is considered as a private
    method. Backends looking to populate this variable should
    do so via calling thisObj._set_best() directly.

    YANG Description: BGP Add-Path advertise best n paths
    """
    if hasattr(v, "_utype"):
      v = v._utype(v)
    try:
      t = YANGDynClass(v,base=RestrictedClassType(base_type=RestrictedClassType(base_type=long, restriction_dict={'range': ['0..4294967295']}, int_size=32), restriction_dict={'range': [u'1..16']}), is_leaf=True, yang_name="best", rest_name="best", parent=self, path_helper=self._path_helper, extmethods=self._extmethods, register_paths=True, extensions={u'tailf-common': {u'cli-full-command': None, u'code-name': u'additional-paths-advertise-set-best', u'cli-full-no': None, u'info': u'BGP Add-Path advertise best n paths'}}, namespace='urn:brocade.com:mgmt:brocade-ip-policy', defining_module='brocade-ip-policy', yang_type='uint32', is_config=True)
    except (TypeError, ValueError):
      raise ValueError({
          'error-string': """best must be of a type compatible with uint32""",
          'defined-type': "uint32",
          'generated-type': """YANGDynClass(base=RestrictedClassType(base_type=RestrictedClassType(base_type=long, restriction_dict={'range': ['0..4294967295']}, int_size=32), restriction_dict={'range': [u'1..16']}), is_leaf=True, yang_name="best", rest_name="best", parent=self, path_helper=self._path_helper, extmethods=self._extmethods, register_paths=True, extensions={u'tailf-common': {u'cli-full-command': None, u'code-name': u'additional-paths-advertise-set-best', u'cli-full-no': None, u'info': u'BGP Add-Path advertise best n paths'}}, namespace='urn:brocade.com:mgmt:brocade-ip-policy', defining_module='brocade-ip-policy', yang_type='uint32', is_config=True)""",
        })

    self.__best = t
    if hasattr(self, '_set'):
      self._set()