You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: server.go
    path of file: ./repos/juju/provider/ec2/internal/testing
    
    the code of the file until where you have to start completion: // Copyright 2021 Canonical Ltd.
// Licensed under the AGPLv3, see LICENCE file for details.

package testing

import (
	"sync"

	"github.com/aws/aws-sdk-go-v2/service/ec2/types"
)

// Server implements an EC2 simulator for use in testing.
type Server struct {
	mu               sync.Mutex
	createRootDisks  bool
	apiCallErrors    map[string]error
	apiCallModifiers map[st
    
func (srv *Server) Reset(withoutZonesOrGroups bool) {
	srv.mu.Lock()
	defer srv.mu.Unlock()

	srv.maxId.reset()
	srv.reqId.reset()
	srv.reservationId.reset()
	srv.groupId.reset()
	srv.vpcId.reset()
	srv.igwId.reset()
	srv.rtbId.reset()
	srv.rtbassocId.reset()
	srv.dhcpOptsId.reset()
	srv.subnetId.reset()
	srv.volumeId.reset()
	srv.ifaceId.reset()
	srv.attachId.reset()

	srv.instanceMutatingCalls.reset()
	srv.groupMutatingCalls.reset()
	srv.volumeMutatingCalls.reset()
	srv.tagsMutatingCalls.reset()

	srv.apiCallErrors = make(map[string]error)
	srv.apiCallModifiers = make(map[string][]func(interface{}))
	srv.attributes = make(map[string][]types.AccountAttributeValue)
	srv.instances = make(map[string]*Instance)
	srv.groups = make(map[string]*securityGroup)
	srv.vpcs = make(map[string]*vpc)
	srv.zones = make(map[string]availabilityZone)
	srv.internetGateways = make(map[string]*internetGateway)
	srv.routeTables = make(map[string]*routeTable)
	srv.subnets = make(map[string]*subnet)
	srv.ifaces = make(map[string]*iface)
	srv.volumes = make(map[string]*volume)
	srv.volumeAttachments = make(map[string]*volumeAttachment)
	srv.reservations = make(map[string]*reservation)

	srv.instanceProfileAssociations = make(map[string]types.IamInstanceProfileAssociation)

	if !withoutZonesOrGroups {
		srv.addDefaultZonesAndGroups()
	}
}