DOC: if and only if

src/caosadvancedtools/table_json_conversion/xlsx_utils.py

@@ -295,7 +295,7 @@ def is_exploded_sheet(sheet: Worksheet) -> bool:
     """Return True if this is a an "exploded" sheet.
 
     An exploded sheet is a sheet whose data entries are LIST valued properties of entries in another
-    sheet.  A sheet is detected as exploded if it has FOREIGN columns.
+    sheet.  A sheet is detected as exploded if and only if it has FOREIGN columns.
     """
     column_types = _get_column_types(sheet)
     return ColumnType.FOREIGN.name in column_types.values()