The Excel file header has different colors to distinguish the usefulness of the data according to the Excel format used.
\uD83D\
...
uDCD8 Color code :
Orange - Mandatory: This data must be present during import.
Blue - Informative: This data is for information only and will not be read during import.
Black - optional: This data will be read if present, but is not mandatory.
Violet - conditional: This data is mandatory under certain conditions.
Red - Forbidden: This data must not be filled in.
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