adjusted preprocessing tests

conftest.py

@@ -66,5 +66,5 @@ def default_session_fixture(request):
 
     # request.addfinalizer(unpatch)
 
-    with mock.patch("multiprocessing.cpu_count", return_value=1):
+    with mock.patch("psutil.cpu_count", return_value=1):
         yield

mlair/run_modules/pre_processing.py

@@ -245,7 +245,7 @@ class PreProcessing(RunEnvironment):
 
         max_process = self.data_store.get("max_number_multiprocessing")
         n_process = min([psutil.cpu_count(logical=False), len(set_stations), max_process])  # use only physical cpus
-        if n_process > 1 and use_multiprocessing:  # parallel solution
+        if n_process > 1 and use_multiprocessing is True:  # parallel solution
             logging.info("use parallel validate station approach")
             pool = multiprocessing.Pool(n_process)
             logging.info(f"running {getattr(pool, '_processes')} processes in parallel")

test/test_run_modules/test_pre_processing.py

@@ -109,7 +109,7 @@ class TestPreProcessing:
         assert caplog.record_tuples[-1] == ('root', 20, PyTestRegex(r'run for \d+:\d+:\d+ \(hh:mm:ss\) to check 6 '
                                                                     r'station\(s\). Found 5/6 valid stations.'))
 
-    @mock.patch("multiprocessing.cpu_count", return_value=3)
+    @mock.patch("psutil.cpu_count", return_value=3)
     @mock.patch("multiprocessing.Pool", return_value=multiprocessing.Pool(3))
     def test_validate_station_parallel(self, mock_pool, mock_cpu, caplog, obj_with_exp_setup):
         pre = obj_with_exp_setup