Lazy Batching Generator

Embedding APIs and databases work best in batches, say 100 texts per request. Write a generator that groups any iterable into batches lazily, so it works on huge files and even infinite streams.

Implement batched(iterable, n):

• Yield tuples of n items. The last tuple may be shorter. Never yield an empty tuple.
• It must be lazy: pull items from iterable only as needed. Don't call list() on the input.
• Raise ValueError if n < 1.
• Don't use itertools.batched. Write it yourself.

Example

list(batched("abcdefg", 3))   # [('a', 'b', 'c'), ('d', 'e', 'f'), ('g',)]