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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 json_get(parsed_json, key):
 """ Retrieves the key from a parsed_json dictionary, or raises an exception if the key is not present """

    if key not in parsed_json:
        raise ValueError("JSON does not contain a {} field".format(key))
    return parsed_json[key]