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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 retrieve_all(self, subset=None):
 """Return a list of all JSSListData elements as full JSSObjects. This can take a long time given a large number of objects, and depending on the size of each object. Subsetting to only include the data you need can improve performance. Args: subset: For objects which support it, a list of sub-tags to request, or an "&" delimited string, (e.g. "general&purchasing"). Default to None. """

        # Attempt to speed this procedure up as much as can be done.

        get_object = self.factory.get_object
        obj_class = self.obj_class

        full_objects = [get_object(obj_class, list_obj.id, subset) for list_obj
                        in self]
        return JSSObjectList(self.factory, obj_class, full_objects)