code: def enable(self, snmp_agent, snmp_location=None, snmp_interface=None):
          
          agent = element_resolver(snmp_agent)
          snmp_interface = [] if not snmp_interface else snmp_interface
          interfaces = self._iface_dict(snmp_interface)
      
          self.engine.data.update(
              snmp_agent_ref=agent,
              snmp_location=snmp_location if snmp_location else '',
              snmp_interface=interfaces)
docs: Enable SNMP on the engine. Specify a list of interfaces
          by ID to enable only on those interfaces. Only interfaces
          that have NDI's are supported.
          
          :param str,Element snmp_agent: the SNMP agent reference for this engine
          :param str snmp_location: the SNMP location identifier for the engine
          :param list snmp_interface: list of interface IDs to enable SNMP
          :raises ElementNotFound: unable to resolve snmp_agent
          :raises InterfaceNotFound: specified interface by ID not found