void removeAddressFromExternalLabel(ProgramDB program, String transactionDescription,
			String library, String label) {
		int txId = program.startTransaction(transactionDescription);
		boolean commit = false;
		ExternalManager externalManager = program.getExternalManager();
		try {
			ExternalLocation externalLocation =
				externalManager.getUniqueExternalLocation(library, label);
			assertNotNull(externalLocation);
			externalLocation.setLocation(externalLocation.getLabel(), null,
				externalLocation.getSource());

			commit = true;
		}
		catch (Exception e) {
			Assert.fail(e.getMessage());
		}
		finally {
			program.endTransaction(txId, commit);
		}

		assertTrue(externalManager.contains(library));
		ExternalLocation externalLocation =
			externalManager.getUniqueExternalLocation(library, label);
		assertNotNull(externalLocation);
		assertEquals(library + "::" + label, externalLocation.toString());
		assertNull(externalLocation.getAddress());
	}
@param program
@param transactionDescription
@param library
@param label
Ghidra/Features/Base/src/test.slow/java/ghidra/app/merge/listing/AbstractExternalMergerTest.java