human
Solve the following python programming problem given the following code:
def get_query_widget_class(descriptor, widget_type = None) : 
    cls = get_widget_class (descriptor, widget_type, 'query', False) 
    if (cls is None) : 
        if ((descriptor.module is not None) and hasattr (descriptor.module, 'get_query_widget_class')) : 
            cls = descriptor.module.get_query_widget_class () 
if (cls is None) : 
            class DefaultQueryWidget (BaseQueryWidget) : 
                def __init__(self, param, parent = None) : 
                    BaseQueryWidget.__init__ (self, get_widget_class (descriptor), ['==', '!='], param, parent) 
return DefaultQueryWidget 
reg = get_module_registry () 
        prefix = get_prefix (reg, reg) 
        return load_cls (cls, prefix) 
return cls 

    
    

    Fix the buggy line: prefix = get_prefix (reg, reg)
assistant
#Here is Python code to fix the buggy line: prefix = get_prefix (reg, reg)
.

prefix = get_prefix (reg, descriptor)