var checkbox1, checkbox2; 
 
function forceOrder( el ) { 
    if ( checkbox1 === undefined ){ 
        checkbox1 = document.getElementById('orderimportant1'); 
        checkbox2 = document.getElementById('orderimportant2'); 
    } 
 
    checkbox1.checked = !el.checked; 
    checkbox2.checked = !el.checked; 
    checkbox1.disabled = el.checked; 
    checkbox2.disabled = el.checked; 
} 
 
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