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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 add_context(self, context, label=None):
 """Append `context` to model Arguments: context (dict):
 Serialised to add Schema: context.json """


        assert isinstance(context, dict)

        item = defaults["common"].copy()
        item.update(defaults["instance"])
        item.update(context)

        item["family"] = None
        item["label"] = context["data"].get("label") or settings.ContextLabel
        item["itemType"] = "instance"
        item["isToggled"] = True
        item["optional"] = False
        item["hasCompatible"] = True

        item = self.add_item(item)
        self.instances.append(item)