private void mapResultsToMyLibs() {
		SymbolTable mySymbolManager = myPgm.getSymbolTable();
		String[] myNames = myExtMgr.getExternalLibraryNames();
		for (String myName : myNames) {
			Symbol librarySymbol = mySymbolManager.getLibrarySymbol(myName);
			long myID = librarySymbol.getID();
			long resultID;
			try {
				resultID = getResultIDFromMyID(myID);
			}
			catch (NoValueException e) {
				resultID = myID;
			}
			if ((resultID != -1) && (resultID != myID)) {
				resultToMyMap.put(resultID, myID);
			}
		}
	}
Populate the reverse map for the Library symbols in the My program.
Ghidra/Features/Base/src/main/java/ghidra/app/merge/listing/ExternalProgramMerger.java