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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 find_duplicate_keys(data):
 """ Find duplicate keys in a layer of ordered pairs. Intended as the object_pairs_hook callable for json.load or loads. :param data: ordered pairs :return: Dictionary with no duplicate keys :raises ValueError if duplicate keys are found """

    out_dict = {}
    for key, value in data:
        if key in out_dict:
            raise ValueError("Duplicate key: {}".format(key))
        out_dict[key] = value
    return out_dict