Switch default backend to ProcessPoolExecutor even when loky is installed. (#59)

Author: tobiasraabe

Diff for: CHANGES.md

@@ -5,10 +5,12 @@ chronological order. Releases follow [semantic versioning](https://semver.org/)
 releases are available on [PyPI](https://pypi.org/project/pytask-parallel) and
 [Anaconda.org](https://anaconda.org/conda-forge/pytask-parallel).
 
-## 0.3.1 - 2023-xx-xx
+## 0.3.1 - 2023-05-27
 
 - {pull}`56` refactors the `ProcessPoolExecutor`.
 - {pull}`57` does some housekeeping.
+- {pull}`59` sets the default backend to `ProcessPoolExecutor` even when loky is
+  installed.
 
 ## 0.3.0 - 2023-01-23
 

Diff for: src/pytask_parallel/backends.py

@@ -46,8 +46,6 @@ class ParallelBackendChoices(enum.Enum):
         PROCESSES = "processes"
         THREADS = "threads"
 
-    PARALLEL_BACKENDS_DEFAULT = ParallelBackendChoices.PROCESSES
-
     PARALLEL_BACKENDS = {
         ParallelBackendChoices.PROCESSES: CloudpickleProcessPoolExecutor,
         ParallelBackendChoices.THREADS: ThreadPoolExecutor,
@@ -72,6 +70,4 @@ class ParallelBackendChoices(enum.Enum):  # type: ignore[no-redef]
         ),
     }
 
-    PARALLEL_BACKENDS_DEFAULT = (
-        ParallelBackendChoices.LOKY  # type: ignore[attr-defined]
-    )
+PARALLEL_BACKENDS_DEFAULT = ParallelBackendChoices.PROCESSES