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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 instantiate_from_config(cfg):
 """Instantiate data types from config"""

    for h in cfg:
        if h.get("type") in data_types:
            raise KeyError("Data type '%s' already exists" % h)
        data_types[h.get("type")] = DataType(h)