code: public static @NotNull IteratorAssert assertThat(@Nullable Iterable<?> actual) {
      Iterator<?> iterator = actual == null ? null : actual.iterator();
      return assertThat(iterator);
    }
docs: Creates a new instance of {@link IteratorAssert}.
  
  @param actual an {@code Iterable} whose contents will be added to a new {@code Collection}.
  @return the created assertion object.