Add a new method, fix bytes_iter

banal/cache.py

@@ -25,6 +25,8 @@ def bytes_iter(obj) -> Iterable[bytes]:
     elif isinstance(obj, (date, datetime)):
         yield _bytes_str(obj.isoformat())
     elif is_mapping(obj):
+        if None in obj:
+            yield from bytes_iter(obj.pop(None))
         for key in sorted(obj.keys()):
             for out in chain(bytes_iter(key), bytes_iter(obj[key])):
                 yield out

banal/lists.py

@@ -1,5 +1,7 @@
-from typing import List, Any
-from collections.abc import Sequence
+from typing import List, Set, Any, TypeVar, Generator
+from collections.abc import Sequence, Iterable
+
+T = TypeVar("T")
 
 
 def is_sequence(obj: Any) -> bool:
@@ -31,6 +33,34 @@ def ensure_list(obj: Any) -> List:
     return [o for o in obj]
 
 
+def chunked_iter(
+    iterable: Iterable[T], batch_size: int = 500
+) -> Generator[List[T], None, None]:
+    """Pick `batch_size` items from an iterable and treat them as a batch list."""
+    batch = list()
+    for item in iterable:
+        batch.append(item)
+        if len(batch) >= batch_size:
+            yield batch
+            batch = list()
+    if len(batch) > 0:
+        yield batch
+
+
+def chunked_iter_sets(
+    iterable: Iterable[T], batch_size: int = 500
+) -> Generator[Set[T], None, None]:
+    """Pick `batch_size` items from an iterable and treat them as a batch set."""
+    batch = set()
+    for item in iterable:
+        batch.add(item)
+        if len(batch) >= batch_size:
+            yield batch
+            batch = set()
+    if len(batch) > 0:
+        yield batch
+
+
 def first(lst: Sequence) -> Any:
     """Return the first non-null element in the list, or None."""
     for item in ensure_list(lst):