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About templates and data markers
An ExcelTemplate ExcelWriter template is an Excel file that contains ExcelWriter data markers. A datamarker is a cell value beginning with %%= that specifies a database colum, variable, or array to insert into the spreadsheet column. Data markers are added to a worksheet in Excel and then bound to data sources in code. ExcelWriter populates the data markers with values from the data sources when the code is executed.
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