human
Solve the following python programming problem given the following code:
def _calculate_sources(self, target) : 
    gentargets = OrderedSet () 
    def add_to_gentargets(target) : 
        if self.is_gentarget (target) : 
            gentargets.add (target) 
self.context.build_graph.walk_transitive_dependency_graph ([target.address], add_to_gentargets, postorder = True) 
    sources_by_base = OrderedDict () 
    for target in gentargets : 
        base = target.target_base 
        if (base not in sources_by_base) : 
            sources_by_base [target] = OrderedSet () 
sources_by_base [base].update (target.sources_relative_to_buildroot ()) 
return sources_by_base 

    
    

    Fix the buggy line: sources_by_base [target] = OrderedSet ()
assistant
#Here is Python code to fix the buggy line: sources_by_base [target] = OrderedSet ()
.

sources_by_base [base] = OrderedSet ()