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 @isTest

private class OpportunityTeamMemberTest {

    @isTest

    static void testReturnCoverage() {

        // Create test data

        Account acc = new Account(Name='Test Acc');

        insert acc;

        Opportunity opp = new Opportunity(

            Name='Test Opp',

            StageName='Prospecting',

            CloseDate=Date.today(),

            AccountId=acc.Id

        );

        insert opp;

        OpportunityTeamMember otm = new OpportunityTeamMember(

            OpportunityId = opp.Id,

            UserId = UserInfo.getUserId(),

            TeamMemberRole = 'Sales Rep'

        );

        insert otm;

        // IMPORTANT

        XLI_TriggerBypass.bypassOpportunityTeamMember = true;

        Test.startTest();

        otm.TeamMemberRole = 'Manager';

        update otm;

        Test.stopTest();

        // Reset flag

        XLI_TriggerBypass.bypassOpportunityTeamMember = false;

    }

}