From 0a8b70a931e0a979de3f7302b54048401da1f593 Mon Sep 17 00:00:00 2001
From: Juan Martin Loyola <jmloyola@outlook.com>
Date: Tue, 12 Oct 2021 16:48:33 -0300
Subject: [PATCH 1/3] Remove MultiLabelBinarizer from DOCSTRING_IGNORE_LIST

---
 maint_tools/test_docstrings.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/maint_tools/test_docstrings.py b/maint_tools/test_docstrings.py
index bb73b3ad3e22f..28f7ee30725a5 100644
--- a/maint_tools/test_docstrings.py
+++ b/maint_tools/test_docstrings.py
@@ -13,7 +13,6 @@
     "LabelPropagation",
     "LabelSpreading",
     "LocallyLinearEmbedding",
-    "MultiLabelBinarizer",
     "MultiTaskElasticNet",
     "MultiTaskElasticNetCV",
     "MultiTaskLasso",

From 35a96d81c5991b73c6575791ab07023bccb48887 Mon Sep 17 00:00:00 2001
From: Juan Martin Loyola <jmloyola@outlook.com>
Date: Tue, 12 Oct 2021 16:48:52 -0300
Subject: [PATCH 2/3] Fix numpydocs from MultiLabelBinarizer

---
 sklearn/preprocessing/_label.py | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/sklearn/preprocessing/_label.py b/sklearn/preprocessing/_label.py
index 2886f1b7f9ecf..18df846ec15fe 100644
--- a/sklearn/preprocessing/_label.py
+++ b/sklearn/preprocessing/_label.py
@@ -692,6 +692,11 @@ class MultiLabelBinarizer(TransformerMixin, BaseEstimator):
         Otherwise it corresponds to the sorted set of classes found
         when fitting.
 
+    See Also
+    --------
+    OneHotEncoder : Encode categorical features using a one-hot aka one-of-K
+        scheme.
+
     Examples
     --------
     >>> from sklearn.preprocessing import MultiLabelBinarizer
@@ -724,11 +729,6 @@ class MultiLabelBinarizer(TransformerMixin, BaseEstimator):
     MultiLabelBinarizer()
     >>> mlb.classes_
     array(['comedy', 'sci-fi', 'thriller'], dtype=object)
-
-    See Also
-    --------
-    OneHotEncoder : Encode categorical features using a one-hot aka one-of-K
-        scheme.
     """
 
     def __init__(self, *, classes=None, sparse_output=False):
@@ -747,7 +747,8 @@ def fit(self, y):
 
         Returns
         -------
-        self : returns this MultiLabelBinarizer instance
+        self : object
+            Returns this MultiLabelBinarizer instance.
         """
         self._cached_dict = None
         if self.classes is None:

From 93a503b360ddcdb79c240745d96c965fb7f81fb1 Mon Sep 17 00:00:00 2001
From: Juan Martin Loyola <jmloyola@outlook.com>
Date: Tue, 12 Oct 2021 16:54:19 -0300
Subject: [PATCH 3/3] Change docstrings to maintain consistency

---
 sklearn/preprocessing/_label.py | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/sklearn/preprocessing/_label.py b/sklearn/preprocessing/_label.py
index 18df846ec15fe..4410988513f39 100644
--- a/sklearn/preprocessing/_label.py
+++ b/sklearn/preprocessing/_label.py
@@ -748,7 +748,7 @@ def fit(self, y):
         Returns
         -------
         self : object
-            Returns this MultiLabelBinarizer instance.
+            Fitted estimator.
         """
         self._cached_dict = None
         if self.classes is None:
@@ -779,7 +779,7 @@ def fit_transform(self, y):
         Returns
         -------
         y_indicator : {ndarray, sparse matrix} of shape (n_samples, n_classes)
-            A matrix such that `y_indicator[i, j] = 1` i.f.f. `classes_[j]`
+            A matrix such that `y_indicator[i, j] = 1` iff `classes_[j]`
             is in `y[i]`, and 0 otherwise. Sparse matrix will be of CSR
             format.
         """
@@ -847,6 +847,10 @@ def _transform(self, y, class_mapping):
         Parameters
         ----------
         y : iterable of iterables
+            A set of labels (any orderable and hashable object) for each
+            sample. If the `classes` parameter is set, `y` will not be
+            iterated.
+
         class_mapping : Mapping
             Maps from label to column index in label indicator matrix.