StructuredDocumentTag.placeholder property. Gets the [BuildingBlock](../../../aspose.words.buildingblocks/buildingblock/) containing placeholder text which should be displayed when this SDT run contents are empty, the associated mapped XML element is empty as specified via the [StructuredDocumentTag.xml_mapping](../xml_mapping/) element or the [StructuredDocumentTag.is_showing_placeholder_text](../is_showing_placeholder_text/) element is ``True``....text for a structured document tag. doc = aw . Document () # Insert...plain text structured document tag of the "PLAIN_TEXT" type, which...