diff --git a/MRdataset/tests/simulate.py b/MRdataset/tests/simulate.py
index 147c044..1529b88 100644
--- a/MRdataset/tests/simulate.py
+++ b/MRdataset/tests/simulate.py
@@ -17,7 +17,9 @@
 THIS_DIR = Path(__file__).parent.resolve()
 
 
-def sample_dicom_dataset(tmp_path='/tmp'):
+def sample_dicom_dataset(tmp_path=None):
+    if not tmp_path:
+        tmp_path = tempfile.gettempdir()
     DATA_ARCHIVE = THIS_DIR / 'resources/example_dicom_data.zip'
     DATA_ROOT = Path(tmp_path)
     output_dir = DATA_ROOT / 'example_dicom_data'
@@ -27,7 +29,9 @@ def sample_dicom_dataset(tmp_path='/tmp'):
     return DATA_ROOT / 'example_dicom_data'
 
 
-def sample_bids_dataset(tmp_path='/tmp'):
+def sample_bids_dataset(tmp_path=None):
+    if not tmp_path:
+        tmp_path = tempfile.gettempdir()
     DATA_ARCHIVE = THIS_DIR / 'resources/example_bids_data.zip'
     if not DATA_ARCHIVE.exists():
         raise FileNotFoundError(f'Please download example datasets from '
@@ -40,7 +44,9 @@ def sample_bids_dataset(tmp_path='/tmp'):
     return DATA_ROOT / 'example_bids_dataset'
 
 
-def sample_vertical_dataset(tmp_path='/tmp'):
+def sample_vertical_dataset(tmp_path=None):
+    if not tmp_path:
+        tmp_path = tempfile.gettempdir()
     DATA_ARCHIVE = THIS_DIR / 'resources/vertical.zip'
     DATA_ROOT = Path(tmp_path)
     output_dir = DATA_ROOT / 'vertical/'
@@ -109,7 +115,7 @@ def make_compliant_bids_dataset(num_subjects,
         try:
             with open(filepath, "r") as read_file:
                 parameters = json.load(read_file)
-        except (FileNotFoundError, ValueError) as e:
+        except (FileNotFoundError, ValueError):
             continue
         parameters['RepetitionTime'] = repetition_time
         parameters['EchoTrainLength'] = echo_train_length
diff --git a/MRdataset/tests/test_base.py b/MRdataset/tests/test_base.py
index a975ad2..4bbe85f 100644
--- a/MRdataset/tests/test_base.py
+++ b/MRdataset/tests/test_base.py
@@ -5,11 +5,8 @@
 import pytest
 from hypothesis import given, settings, HealthCheck
 
-from MRdataset import BaseDataset, import_dataset
-from MRdataset.dicom import DicomDataset
 from MRdataset.tests.conftest import dcm_dataset_strategy, \
     vertical_dataset_strategy
-from MRdataset.tests.simulate import make_compliant_test_dataset
 from MRdataset.utils import convert2ascii
 
 THIS_DIR = Path(__file__).parent.resolve()
diff --git a/MRdataset/tests/test_bids.py b/MRdataset/tests/test_bids.py
index 525f09b..63b5ca8 100644
--- a/MRdataset/tests/test_bids.py
+++ b/MRdataset/tests/test_bids.py
@@ -36,7 +36,7 @@ def test_dataset(num_subjects,
 
     for seq_id in seq_ids:
         mrd_num_subjects = set()
-        for subject, session, run, seq in mrd.traverse_horizontal(seq_id):
+        for subject, _, _, seq in mrd.traverse_horizontal(seq_id):
             mrd_num_subjects.add(subject)
             assert seq['RepetitionTime'].get_value() == repetition_time
             assert seq['EchoTrainLength'].get_value() == echo_train_length
@@ -49,18 +49,18 @@ def test_dataset(num_subjects,
 def test_config_dict():
     fake_ds_dir = make_compliant_bids_dataset(1, 1, 1, 1)
     with pytest.raises(FileNotFoundError):
-        mrd = import_dataset(fake_ds_dir, config_path='non-existent.json',
-                             output_dir=fake_ds_dir, name='test_dataset',
-                             ds_format='bids')
+        import_dataset(fake_ds_dir, config_path='non-existent.json',
+                       output_dir=fake_ds_dir, name='test_dataset',
+                       ds_format='bids')
 
 
 def test_invalid_output_dir():
     fake_ds_dir = make_compliant_bids_dataset(1, 1, 1, 1)
     with pytest.raises(TypeError):
-        mrd = import_dataset(fake_ds_dir,
-                             config_path=THIS_DIR / 'resources/bids-config.json',
-                             output_dir=1, name='test_dataset',
-                             ds_format='bids')
+        import_dataset(fake_ds_dir,
+                       config_path=THIS_DIR / 'resources/bids-config.json',
+                       output_dir=1, name='test_dataset',
+                       ds_format='bids')
 
 
 def test_invalid_datatype():