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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 main():
 """Pylint JSON to HTML Main Entry Point"""

    parser = build_command_parser()
    options = parser.parse_args()
    file_pointer = options.filename
    input_format = options.input_format

    with file_pointer:
        json_data = json.load(file_pointer)

    if input_format == SIMPLE_JSON:
        report = Report(json_data)
    elif input_format == EXTENDED_JSON:
        report = Report(
            json_data.get('messages'),
            json_data.get('stats'),
            json_data.get('previous'))

    print(report.render(), file=options.output)