A factory receives multiple batches of parts, but some parts are defective and must be removed to identify high-quality components, which should be displayed without duplicates.

The PartBatch class represents a batch of parts, with a batch name (batchName) and a list of parts (parts). To access the list of parts from a batch, you use the getParts() method, and to retrieve the batch name, you use the getBatchName() method.

1. Extract all parts from each batch using flatMap() method.
2. Filter out defective parts by checking if the part name starts with Defective using filter() method.
3. Remove duplicate parts to get a list of unique quality parts using distinct() method.