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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_loads(data):
 """Load json data, allowing - to represent stdin."""

    if data is None:
        return ""

    if data == "-":
        return json.load(sys.stdin)
    elif os.path.exists(data):
        with open(data, 'r') as handle:
            return json.load(handle)
    else:
        return json.loads(data)