code: public <A extends Appendable> A appendTo(A appendable, Iterable<? extends Entry<?, ? extends Collection<?>>> entries)
  			throws IOException {
  		//    checkNotNull(appendable);
  		Iterator<? extends Entry<?, ? extends Collection<?>>> iterator = entries.iterator();
  		if (iterator.hasNext()) {
  			Entry<?, ? extends Collection<?>> entry = iterator.next();
  			appendable.append(toString(entry.getKey()));
  			appendable.append(keyValueSeparator);
  			entryJoiner.appendTo(appendable, entry.getValue());
  			while (iterator.hasNext()) {
  				appendable.append(separator);
  				Entry<?, ? extends Collection<?>> e = iterator.next();
  				appendable.append(toString(e.getKey()));
  				appendable.append(keyValueSeparator);
  				entryJoiner.appendTo(appendable, e.getValue());
  			}
  		}
  		return appendable;
  	}
docs: Appends the string representation of each entry in {@code entries}, using the previously configured separator and
  key-value separator, to {@code appendable}.