human
Solve the following python programming problem given the following code:
def adapt_criterion_to_null(crit, nulls) : 
    'given criterion containing bind params, convert selected elements
    to IS NULL.

    ' 
    def visit_binary(binary) : 
        if (isinstance (binary.left, BindParameter) and (binary.left._identifying_key in nulls)) : 
            binary.left = binary.right 
            binary.right = Null () 
            binary.operator = operators.is_ 
            binary.negate = operators.isnot 
else : 
            if (isinstance (binary.right, BindParameter) and (binary.right._identifying_key in nulls)) : 
                binary.right = Null () 
                binary.operator = operators.is_ 
                binary.negate = operators.isnot 
return visitors.cloned_traverse (nulls, { 
        
}, { 
        'binary' : visit_binary, 
}) 

    
    

    Fix the buggy line: return visitors.cloned_traverse (nulls, {
assistant
#Here is Python program to fix the buggy line: return visitors.

return visitors.cloned_traverse (crit, {