@isTest
public class AssignTest {
    @isTest static void testMthd(){
        
        List<Opportunity>oppl=new List<Opportunity>();
        Opportunity op=new Opportunity();
        op.CloseDate=Date.today();
        op.Name='Yumi';
       
        op.StageName='Closed Won';
        oppl.add(op);
        insert oppl;
       
         List<Task> tasksToInsert = new List<Task>();
         for (Opportunity opps :oppl) {
        if (opps.StageName == 'Closed Won') {
            Task newTask = new Task();
            newTask.Subject = 'Opportunity Closed Won ho gyi hai bhai';
            newTask.Description = 'Account Name: ' + opps.Account.Name + '\nOpportunity Name: ' + opps.Name + '\nClose Date: ' + opps.CloseDate;
            tasksToInsert.add(newTask);
        }
    }
    if (!tasksToInsert.isEmpty()) {
        insert tasksToInsert;
    }
        
    }
    

}