Minimum requirement for pyyaml

.github/conda/meta.yaml

@@ -26,7 +26,7 @@ requirements:
     - regex !=2019.12.17
     - protobuf
     - tokenizers >=0.10.1,<0.11.0
-    - pyyaml
+    - pyyaml >= 5.1
   run:
     - python
     - numpy >=1.17
@@ -41,7 +41,7 @@ requirements:
     - regex !=2019.12.17
     - protobuf
     - tokenizers >=0.10.1,<0.11.0
-    - pyyaml
+    - pyyaml >= 5.1
 
 test:
   imports:

setup.py

@@ -119,7 +119,7 @@ _deps = [
     "parameterized",
     "protobuf",
     "psutil",
-    "pyyaml",
+    "pyyaml>=5.1",
     "pydantic",
     "pytest",
     "pytest-sugar",

src/transformers/dependency_versions_table.py

@@ -36,7 +36,7 @@ deps = {
     "parameterized": "parameterized",
     "protobuf": "protobuf",
     "psutil": "psutil",
-    "pyyaml": "pyyaml",
+    "pyyaml": "pyyaml>=5.1",
     "pydantic": "pydantic",
     "pytest": "pytest",
     "pytest-sugar": "pytest-sugar",