diff --git a/docs/troubleshooting.rst b/docs/troubleshooting.rst
index e79b3c1..97d08a2 100644
--- a/docs/troubleshooting.rst
+++ b/docs/troubleshooting.rst
@@ -143,6 +143,7 @@
 
   import os
 
+
   def test_something(fs):
       # the temp directory is always present at test start
       assert len(os.listdir("/")) == 1
@@ -166,6 +167,7 @@
 
   from pyfakefs.fake_filesystem_unittest import TestCase
 
+
   class SomeTest(TestCase):
       def setUp(self):
           self.setUpPyfakefs(allow_root_user=False)
@@ -191,11 +193,12 @@
 
   def test_mock_open_incorrect(mocker, fs):
       # causes a recursion error
-      mocker.patch('builtins.open', mocker.mock_open(read_data="content"))
+      mocker.patch("builtins.open", mocker.mock_open(read_data="content"))
+
 
   def test_mock_open_correct(fs, mocker):
       # works correctly
-      mocker.patch('builtins.open', mocker.mock_open(read_data="content"))
+      mocker.patch("builtins.open", mocker.mock_open(read_data="content"))
 
 
 .. _`multiprocessing`: https://docs.python.org/3/library/multiprocessing.html