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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):
 """Deserialize from json. Args: json: a dict of json compatible fields. Returns: a KeyRanges object. Raises: ValueError: if the json is invalid. """

    if json["name"] in _KEYRANGES_CLASSES:
      return _KEYRANGES_CLASSES[json["name"]].from_json(json)
    raise ValueError("Invalid json %s", json)