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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_changes(self, changers, in_hierarchy=False, resources=None, task_handle=taskhandle.NullTaskHandle()):
 """Get changes caused by this refactoring `changers` is a list of `_ArgumentChanger`\s. If `in_hierarchy` is `True` the changers are applyed to all matching methods in the class hierarchy. `resources` can be a list of `rope.base.resource.File`\s that should be searched for occurrences; if `None` all python files in the project are searched. """

        function_changer = _FunctionChangers(self.pyname.get_object(),
                                             self._definfo(), changers)
        return self._change_calls(function_changer, in_hierarchy,
                                  resources, task_handle)