code: def add_rule(self, ip_protocol, from_port, to_port,
                   src_group_name, src_group_owner_id, cidr_ip):
          
          rule = IPPermissions(self)
          rule.ip_protocol = ip_protocol
          rule.from_port = from_port
          rule.to_port = to_port
          self.rules.append(rule)
          rule.add_grant(src_group_name, src_group_owner_id, cidr_ip)
docs: Add a rule to the SecurityGroup object.  Note that this method
          only changes the local version of the object.  No information
          is sent to EC2.