fix style issues

capa/helpers.py

@@ -5,7 +5,6 @@
 # Unless required by applicable law or agreed to in writing, software distributed under the License
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
-import os
 import json
 import inspect
 import logging

scripts/show-features.py

@@ -83,7 +83,7 @@ import capa.features.address
 import capa.features.extractors.pefile
 from capa.helpers import get_auto_format, log_unsupported_runtime_error
 from capa.features.common import FORMAT_AUTO, FORMAT_FREEZE, DYNAMIC_FORMATS, is_global_feature
-from capa.features.extractors.base_extractor import FeatureExtractor, StaticFeatureExtractor, DynamicFeatureExtractor, FunctionHandle
+from capa.features.extractors.base_extractor import FunctionHandle, StaticFeatureExtractor, DynamicFeatureExtractor
 
 logger = logging.getLogger("capa.show-features")
 
@@ -109,7 +109,7 @@ def main(argv=None):
         return -1
 
     try:
-        taste = capa.helpers.get_file_taste(Path(args.sample))
+        _ = capa.helpers.get_file_taste(Path(args.sample))
     except IOError as e:
         logger.error("%s", str(e))
         return -1

tests/fixtures.py

@@ -6,6 +6,7 @@
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
 
+import os
 import binascii
 import contextlib
 import collections

tests/test_cape_features.py

@@ -6,7 +6,6 @@
 #  is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and limitations under the License.
 import fixtures
-from fixtures import scope, sample
 
 
 @fixtures.parametrize(