Can u help me to write test class


/**
 * Using without sharing as need to run query on Organization table
 */
public without sharing class Utilities {

    //Get instance from INSTANCE.visual.force.com page so we can build
    public Static String getInstance(){
        String instance = '';
        Organization o = [SELECT OrganizationType, InstanceName FROM Organization limit 1];
        String orgType = o.OrganizationType;
        String insName = o.InstanceName;
        if(orgType == 'Developer Edition' || insName.startsWithIgnoreCase('cs')){
            List<String> parts = ApexPages.currentPage().getHeaders().get('Host').split('\\.');
            instance = parts[parts.size() - 4] + '.';
        }
        return instance;
    }
    //Needed in cases if current org is sandbox
    public static String getSubdomainPrefix(){
        Organization o = [SELECT OrganizationType, InstanceName FROM Organization limit 1];
        String orgType = o.OrganizationType;
        String insName = o.InstanceName;
        if(insName.startsWithIgnoreCase('cs')){
            return UserInfo.getUserName().substringAfterLast('.')+ '-';
        }
        return '';
    }
}

 <aura:attribute name="accVal" type="Account[]" />
    <aura:handler name="init" value="{!this}" action="{!c.doInit}"/>
    <lightning:accordion aura:id="accordion" allowMultipleSectionsOpen="true">
        <aura:iteration items="{!v.accVal}" var="acc">
            <lightning:accordionSection name="{acc.Name}" >
               
            </lightning:accordionSection>
        </aura:iteration>
        
    </lightning:accordion>