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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 from_json(cls, json_dump):
 """ How to get a context from a json dump """

        context = cls()
        if json_dump is None:
            return None
        ctxt = json.loads(json_dump)
        for k in ctxt:
            context[k] = ctxt[k]
        return context