Bump required Python 3.7 -> 3.8, drop TF1 support (#1668)

Closes #1326

.github/workflows/black.yml

@@ -17,7 +17,7 @@ jobs:
     - uses: actions/checkout@v4
     - uses: actions/setup-python@v5
       with:
-        python-version: 3.7
+        python-version: 3.8
         cache: 'pip'
         cache-dependency-path: '.github/workflows/black.yml'
     - run: pip install black==22.3.0

.github/workflows/main.yml

@@ -92,7 +92,7 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
-          - 3.7
+          - 3.8
         action:
           - TEST=Dataset
           - TEST=fork_exec
@@ -158,7 +158,7 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
-          - 3.7
+          - 3.8
         tf-version:
           - 2.10.0
         action:
@@ -174,23 +174,11 @@ jobs:
           - TEST=TFUtil
           - TEST=tools
         include:
-          - action: TEST=TFUtil
-            python-version: 3.7
-            tf-version: 1.15.3
           - action: TEST=TFEngine
-            python-version: 3.7
-            tf-version: 1.15.3
-          - action: TEST=TFEngine
-            python-version: 3.7
+            python-version: 3.8
             tf-version: 2.3.0
-          - action: TEST=TFNativeOp
-            python-version: 3.7
-            tf-version: 1.14.0
-          - action: TEST=TFNetworkSigProcLayer
-            python-version: 3.7
-            tf-version: 1.15.3
           - action: TEST=demos RETURNN_DISABLE_TORCH=1
-            python-version: 3.7
+            python-version: 3.8
             tf-version: 2.3.0
 
     steps:
@@ -221,7 +209,7 @@ jobs:
 
         pip install --user pytest
 
-        if [[ "${{matrix.tf-version}}" == 2.[0123].* || "${{matrix.tf-version}}" == 1.* ]]; then
+        if [[ "${{matrix.tf-version}}" == 2.[0123].* ]]; then
           # Older TF needs older NumPy version.
           # https://github.com/rwth-i6/returnn/pull/1160#issuecomment-1284537803
           pip install --user numpy==1.19.5
@@ -358,7 +346,7 @@ jobs:
         include:
           # Some selected tests (but not all) with some other versions.
           - action: TEST=rf_base
-            python-version: 3.7
+            python-version: 3.8
             torch-version: 1.13.1
             tf-version: 2.10.0
 

.github/workflows/publish.yml

@@ -26,7 +26,7 @@ jobs:
 
     - uses: actions/setup-python@v5
       with:
-        python-version: 3.7
+        python-version: 3.8
 
     - name: Install Python deps
       run: |

CHANGELOG.md

@@ -6,6 +6,10 @@ or any changes which could potentially break or change the behavior of existing
 This is intentionally kept short. For a full change log, just see the Git log.
 
 
+## 2024-12-13: Bump min Python version from 3.7 to 3.8 ([issue #1326](https://github.com/rwth-i6/returnn/issues/1326))
+
+This also drops support for TF 1.x.
+
 ## 2024-06-07: `VariableDataset`
 
 Custom subdataset per subepoch based on user-provided function.

CONTRIBUTING.md

@@ -29,7 +29,7 @@ General rules when contributing to the code of RETURNN:
   and in general to use newer TF features (even maybe TF >=2),
   as long as your new feature (new layer or so) is just optional.
   For older TF support, `TFCompat.py` might be helpful. (See code for examples.)
-* We support Python >=3.7 ([discussion](https://github.com/rwth-i6/returnn/issues/487)).
+* We support Python >=3.8 ([discussion](https://github.com/rwth-i6/returnn/issues/1326)).
 
 About new features:
 

README.rst

@@ -72,3 +72,15 @@ Questions can also be asked on
 
 .. image:: https://github.com/rwth-i6/returnn/workflows/CI/badge.svg
     :target: https://github.com/rwth-i6/returnn/actions
+
+Dependencies
+============
+
+pip dependencies are listed in ``requirements.txt`` and ``requirements-dev``,
+although some parts of the code may require additional dependencies (e.g. ``librosa``, ``resampy``) on-demand.
+
+RETURNN supports Python >= 3.8. Bumps to the minimum Python version are listed in `CHANGELOG.md <https://github.com/rwth-i6/returnn/blob/master/CHANGELOG.md>`__.
+
+TensorFlow-based setups require TensorFlow >= 2.2.
+
+PyTorch-based setups require Torch >= 1.0.

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.black]
 line-length = 120
-target-version = ["py37"]  # https://github.com/rwth-i6/returnn/issues/487
+target-version = ["py38"]  # https://github.com/rwth-i6/returnn/issues/1326
 extend-exclude = '''
 /(
     # All Git submodules, see .gitmodules.

tests/PyCharm.idea/inspectionProfiles/Project_Default.xml

@@ -4,10 +4,9 @@
     <inspection_tool class="PyCompatibilityInspection" enabled="true" level="WARNING" enabled_by_default="true">
       <option name="ourVersions">
         <value>
-          <list size="3">
-            <item index="0" class="java.lang.String" itemvalue="3.7" />
-            <item index="1" class="java.lang.String" itemvalue="3.8" />
-            <item index="2" class="java.lang.String" itemvalue="3.9" />
+          <list size="2">
+            <item index="0" class="java.lang.String" itemvalue="3.8" />
+            <item index="1" class="java.lang.String" itemvalue="3.9" />
           </list>
         </value>
       </option>

tests/test_Log.py

@@ -52,9 +52,12 @@ def filter_out(ls):
     i = 0
     while i < len(ls):
         s = ls[i]
-        if "tensorflow/core/" in s or "tensorflow/stream_executor/" in s:  # some TF warnings
+        if any(f"{l} tensorflow/" in s for l in "IWE"):  # some TF warnings
             i += 1
             continue
+        elif "SyntaxWarning" in s:
+            i += 2
+            continue
         # RuntimeWarning|FutureWarning are warnings and they include the code-line in the next output line
         if i + 1 < len(ls) and ls[i + 1].startswith("  "):
             if re.match(".*:\\d+: RuntimeWarning: numpy.*", s) or re.match(".*:\\d+: FutureWarning: .*", s):