human
Solve the following python programming problem given the following code:
def __init__(self, **kwargs) : 
    super (CompoundSelectionBehavior, self).__init__ (** kwargs) 
    def ensure_single_select(* l) : 
        if ((not self.multiselect) and (len (self.selected_nodes) > 1)) : 
            self.clear_selection () 
update_counts = self._update_counts 
    update_counts () 
    fbind = self.fbind 
    fbind ('multiselect', ensure_single_select) 
    fbind ('page_count', update_counts) 
    fbind ('up_count', ensure_single_select) 
    fbind ('right_count', update_counts) 
    fbind ('scroll_count', update_counts) 

    
    

    Fix the buggy line: fbind ('up_count', ensure_single_select)
assistant
#Here is Python code to fix the buggy line: fbind ('up_count', ensure_single_select)
.

fbind ('up_count', update_counts)