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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(j):
 """ load an nparray object from a json-formatted string @parameter str j: json-formatted string """

    if isinstance(j, dict):
        return from_dict(j)

    if not (isinstance(j, str) or isinstance(j, unicode)):
        raise TypeError("argument must be of type str")

    return from_dict(json.loads(j))