refactor python in GH actions (#5281)

* refactor python in GH actions

* .
* .

Author: Borda

.github/workflows/ci_test-full.yml

@@ -47,26 +47,47 @@ jobs:
       if: runner.os == 'windows'
       run: |
         # remove Horovod from requirements
-        python -c "fname = 'requirements/extra.txt' ; lines = [line for line in open(fname).readlines() if not line.startswith('horovod')] ; open(fname, 'w').writelines(lines)"
+        fname = 'requirements/extra.txt'
+        lines = [line for line in open(fname).readlines() if not line.startswith('horovod')]
+        open(fname, 'w').writelines(lines)
+      shell: python
 
     # versions <= 1.3 may have issues on mac with some BLAS ops due to missing mkl (https://github.com/pytorch/pytorch/issues/18996)
     - name: Adjust minimal for Python 3.8 and MacOS
       if: matrix.requires == 'minimal' && (runner.os == 'macOS' || matrix.python-version == 3.8)
       run : |
-        python -c "fname = 'requirements.txt' ; req = open(fname).read().replace('torch>=1.3', 'torch>=1.4') ; open(fname, 'w').write(req)"
-        python -c "fname = 'requirements/examples.txt' ; req = open(fname).read().replace('torchvision>=0.4.1', 'torchvision>=0.5.0') ; open(fname, 'w').write(req)"
-        python -c "fname = 'requirements/extra.txt' ; req = open(fname).read().replace('torchtext>=0.3.1', 'torchtext>=0.5.0') ; open(fname, 'w').write(req)"
+        fname = 'requirements.txt'
+        req = open(fname).read().replace('torch>=1.3', 'torch>=1.4')
+        open(fname, 'w').write(req)
+
+        fname = 'requirements/examples.txt'
+        req = open(fname).read().replace('torchvision>=0.4.1', 'torchvision>=0.5.0')
+        open(fname, 'w').write(req)
+
+        fname = 'requirements/extra.txt'
+        req = open(fname).read().replace('torchtext>=0.3.1', 'torchtext>=0.5.0')
+        open(fname, 'w').write(req)
+      shell: python
 
     - name: Set min. dependencies
       if: matrix.requires == 'minimal'
       run: |
-        python -c "fname = 'requirements.txt' ; req = open(fname).read().replace('>=', '==') ; open(fname, 'w').write(req)"
-        python -c "fname = 'requirements/extra.txt' ; req = open(fname).read().replace('>=', '==') ; open(fname, 'w').write(req)"
-        python -c "fname = 'requirements/loggers.txt' ; req = open(fname).read().replace('>=', '==') ; open(fname, 'w').write(req)"
-        python -c "fname = 'requirements/test.txt' ; req = open(fname).read().replace('>=', '==') ; open(fname, 'w').write(req)"
-        python -c "fname = 'requirements/examples.txt' ; req = open(fname).read().replace('>=', '==') ; open(fname, 'w').write(req)"
+        files = (
+            'requirements.txt',
+            'requirements/extra.txt',
+            'requirements/loggers.txt',
+            'requirements/test.txt',
+            'requirements/examples.txt',
+        )
+        for fname in files:
+            req = open(fname).read().replace('>=', '==')
+            open(fname, 'w').write(req)
+
         # remove Fairscale from requirements
-        python -c "fname = 'requirements/extra.txt' ; lines = [line for line in open(fname).readlines() if 'fairscale' not in line] ; open(fname, 'w').writelines(lines)"
+        fname = 'requirements/extra.txt'
+        lines = [line for line in open(fname).readlines() if 'fairscale' not in line]
+        open(fname, 'w').writelines(lines)
+      shell: python
 
     # Note: This uses an internal pip API and may not always work
     # https://github.com/actions/cache/blob/master/examples.md#multiple-oss-in-a-workflow