diff --git a/src/ocrmypdf/_sync.py b/src/ocrmypdf/_sync.py
index b51238a1..c02543b7 100644
--- a/src/ocrmypdf/_sync.py
+++ b/src/ocrmypdf/_sync.py
@@ -189,7 +189,7 @@ def worker_init(queue):
     root.addHandler(h)
 
 
-def worker_thread_init(queue):
+def worker_thread_init(_queue):
     pass
 
 
@@ -301,7 +301,7 @@ def exec_concurrent(context):
 class NeverRaise(Exception):
     """An exception that is never raised"""
 
-    pass
+    pass  # pylint: disable=unnecessary-pass
 
 
 def run_pipeline(options, api=False):
diff --git a/src/ocrmypdf/exec/tesseract.py b/src/ocrmypdf/exec/tesseract.py
index 03bf037d..05e3266e 100644
--- a/src/ocrmypdf/exec/tesseract.py
+++ b/src/ocrmypdf/exec/tesseract.py
@@ -17,10 +17,8 @@
 
 import os
 import shutil
-import sys
 from collections import namedtuple
 from contextlib import suppress
-from functools import lru_cache
 from os import fspath
 from subprocess import PIPE, STDOUT, CalledProcessError, TimeoutExpired, run
 
diff --git a/src/ocrmypdf/optimize.py b/src/ocrmypdf/optimize.py
index bfe027af..bb1269db 100644
--- a/src/ocrmypdf/optimize.py
+++ b/src/ocrmypdf/optimize.py
@@ -549,11 +549,11 @@ def main(infile, outfile, level, jobs=1):
         """Emulate ocrmypdf's options"""
 
         def __init__(
-            self, input_file, jobs, optimize, jpeg_quality, png_quality, jb2lossy
+            self, input_file, jobs, optimize_, jpeg_quality, png_quality, jb2lossy
         ):
             self.input_file = input_file
             self.jobs = jobs
-            self.optimize = optimize
+            self.optimize = optimize_
             self.jpeg_quality = jpeg_quality
             self.png_quality = png_quality
             self.jbig2_page_group_size = 0
@@ -564,7 +564,7 @@ def main(infile, outfile, level, jobs=1):
     options = OptimizeOptions(
         input_file=infile,
         jobs=jobs,
-        optimize=int(level),
+        optimize_=int(level),
         jpeg_quality=0,  # Use default
         png_quality=0,
         jb2lossy=False,
diff --git a/tests/test_main.py b/tests/test_main.py
index 399d0662..79625d12 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -217,7 +217,7 @@ def test_skip_ocr(spoof_tesseract_cache, resources, outpdf):
     assert pdfinfo[0].has_text
 
 
-def test_redo_ocr(spoof_tesseract_cache, resources, outpdf):
+def test_redo_ocr(resources, outpdf):
     in_ = resources / 'graph_ocred.pdf'
     before = PdfInfo(in_, detailed_page_analysis=True)
     out = outpdf
diff --git a/tests/test_validation.py b/tests/test_validation.py
index e5e3c8f9..5413e375 100644
--- a/tests/test_validation.py
+++ b/tests/test_validation.py
@@ -16,7 +16,7 @@
 # along with OCRmyPDF.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
-from unittest.mock import MagicMock, patch, call
+from unittest.mock import patch
 
 import pytest
 
@@ -135,6 +135,7 @@ def test_no_progress_bar(progress_bar, resources):
     with patch('ocrmypdf.pdfinfo.info.tqdm', autospec=True) as tqdmpatch:
         vd.check_options(opts)
         pdfinfo = PdfInfo(opts.input_file, progbar=opts.progress_bar)
+        assert pdfinfo is not None
         assert tqdmpatch.called
         _args, kwargs = tqdmpatch.call_args
         assert kwargs['disable'] != progress_bar