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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 table_preview(table_name):
 """ Returns the first five rows of a table as JSON. Inlcudes all columns. Uses Pandas' "split" JSON format. """

    preview = orca.get_table(table_name).to_frame().head()
    return (
        preview.to_json(orient='split', date_format='iso'),
        200,
        {'Content-Type': 'application/json'})