Pin black to 21.4b0

setup.py

@@ -86,7 +86,7 @@ if stale_egg_info.exists():
 # 2. once modified, run: `make deps_table_update` to update src/transformers/dependency_versions_table.py
 _deps = [
     "Pillow",
-    "black==20.8b1",
+    "black==21.4b0",
     "cookiecutter==1.7.2",
     "dataclasses",
     "datasets",

src/transformers/dependency_versions_table.py

@@ -3,7 +3,7 @@
 # 2. run `make deps_table_update``
 deps = {
     "Pillow": "Pillow",
-    "black": "black==20.8b1",
+    "black": "black==21.4b0",
     "cookiecutter": "cookiecutter==1.7.2",
     "dataclasses": "dataclasses",
     "datasets": "datasets",