@Override
	public boolean isExternal() {
		Symbol parentSymbol = getParentSymbol();
		return parentSymbol != null ? parentSymbol.isExternal() : false;
	}
Construct a Ghidra Class symbol from an existing symbol record
@param symbolMgr the symbol manager
@param cache symbol object cache
@param record the record associated with the symbol.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/symbol/ClassSymbol.java