added documentation

Signed-off-by: Lukas Folle <lukas.folle@snke.com>

Author: lukas-folle-snkeos

docs/source/transforms.rst

@@ -37,6 +37,11 @@ Generic Interfaces
 .. autoclass:: MultiSampleTrait
     :members:
 
+`ReduceTrait`
+^^^^^^^^^^^^^^^^^^
+.. autoclass:: ReduceTrait
+    :members:
+
 `Randomizable`
 ^^^^^^^^^^^^^^
 .. autoclass:: Randomizable
@@ -1252,6 +1257,12 @@ Utility
     :members:
     :special-members: __call__
 
+`FlattenSequence`
+""""""""""""""""""""""""
+.. autoclass:: FlattenSequence
+    :members:
+    :special-members: __call__
+
 Dictionary Transforms
 ---------------------
 
@@ -2337,6 +2348,12 @@ Utility (Dict)
     :members:
     :special-members: __call__
 
+`FlattenSequenced`
+"""""""""""""""""""""""""
+.. autoclass:: FlattenSequenced
+    :members:
+    :special-members: __call__
+
 
 MetaTensor
 ^^^^^^^^^^

monai/transforms/utility/array.py

@@ -1954,6 +1954,22 @@ def inverse(self, data: torch.Tensor) -> torch.Tensor:
 
 
 class FlattenSequence(Transform, ReduceTrait):
+    """
+    Flatten a nested sequence (list or tuple) by one level.
+    If the input is a sequence of sequences, it will flatten them into a single sequence.
+    Non-nested sequences and other data types are returned unchanged.
+
+    For example:
+
+    .. code-block:: python
+
+        flatten = FlattenSequence()
+        data = [[1, 2], [3, 4], [5, 6]]
+        print(flatten(data))
+        [1, 2, 3, 4, 5, 6]
+
+    """
+
     def __init__(self):
         super().__init__()
 

monai/transforms/utility/dictionary.py

@@ -1911,6 +1911,15 @@ def inverse(self, data: Mapping[Hashable, torch.Tensor]) -> dict[Hashable, torch
 
 
 class FlattenSequenced(MapTransform, ReduceTrait):
+    """
+    Dictionary-based wrapper of :py:class:`monai.transforms.FlattenSequence`.
+
+    Args:
+        keys: keys of the corresponding items to be transformed.
+            See also: monai.transforms.MapTransform
+        allow_missing_keys:
+            Don't raise exception if key is missing.
+    """
     def __init__(
         self,
         keys: KeysCollection,