private Set<String> getFIDNamesThatDontExistSomewhereElse(Program program,
			Iterator<String> iter) {

		Set<String> unusedNames = new HashSet<String>();
		SymbolTable symbolTable = program.getSymbolTable();
		while (iter.hasNext()) {
			String name = iter.next();
			if (!nameExistsSomewhereElse(symbolTable, name)) {
				unusedNames.add(name);
				if (unusedNames.size() > MAGIC_MULTIPLE_MATCH_LIMIT) {
					break;
				}
			}
		}
		return unusedNames;
	}
Takes a set of FID matching names and returns a subset that includes only names that don't exist
somewhere else in the program.
Ghidra/Features/FunctionID/src/main/java/ghidra/feature/fid/cmd/ApplyFidEntriesCommand.java