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: config.go
    path of file: ./repos/octant/vendor/github.com/Azure/go-autorest/autorest/adal
    
    the code of the file until where you have to start completion: package adal

// Copyright 2017 Microsoft Corporation
//
//  Licensed under the Apache License, Version 2.0 (the "License");
//  you may not use this file except in compliance with the License.
//  You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the Lice
    
func NewMultiTenantOAuthConfig(activeDirectoryEndpoint, primaryTenantID string, auxiliaryTenantIDs []string, options OAuthOptions) (MultiTenantOAuthConfig, error) {
	if len(auxiliaryTenantIDs) == 0 || len(auxiliaryTenantIDs) > 3 {
		return nil, errors.New("must specify one to three auxiliary tenants")
	}
	mtCfg := multiTenantOAuthConfig{
		cfgs: make([]*OAuthConfig, len(auxiliaryTenantIDs)+1),
	}
	apiVer := options.apiVersion()
	pri, err := NewOAuthConfigWithAPIVersion(activeDirectoryEndpoint, primaryTenantID, &apiVer)
	if err != nil {
		return nil, fmt.Errorf("failed to create OAuthConfig for primary tenant: %v", err)
	}
	mtCfg.cfgs[0] = pri
	for i := range auxiliaryTenantIDs {
		aux, err := NewOAuthConfig(activeDirectoryEndpoint, auxiliaryTenantIDs[i])
		if err != nil {
			return nil, fmt.Errorf("failed to create OAuthConfig for tenant '%s': %v", auxiliaryTenantIDs[i], err)
		}
		mtCfg.cfgs[i+1] = aux
	}
	return mtCfg, nil
}