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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 _write_ieeg_json(output_file):
 """Use only required fields """

    dataset_info = {
        "TaskName": "unknown",
        "Manufacturer": "n/a",
        "PowerLineFrequency": 50,
        "iEEGReference": "n/a",
        }

    with output_file.open('w') as f:
        dump(dataset_info, f, indent=' ')