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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 read_json_file(fpath):
 """ Read a JSON file from ``fpath``; raise an exception if it doesn't exist. :param fpath: path to file to read :type fpath: str :return: deserialized JSON :rtype: dict """

    if not os.path.exists(fpath):
        raise Exception('ERROR: file %s does not exist.' % fpath)
    with open(fpath, 'r') as fh:
        raw = fh.read()
    res = json.loads(raw)
    return res