diff -r 57875cf423c9 -r 2372284d9457 tests/artifacts/scripts/generate-churning-bundle.py
--- a/tests/artifacts/scripts/generate-churning-bundle.py	Sat Oct 05 10:29:34 2019 -0400
+++ b/tests/artifacts/scripts/generate-churning-bundle.py	Sun Oct 06 09:45:02 2019 -0400
@@ -39,15 +39,17 @@
 #
 # At each revision, the beginning on the file change,
 # and set of other lines changes too.
-FILENAME='SPARSE-REVLOG-TEST-FILE'
+FILENAME = 'SPARSE-REVLOG-TEST-FILE'
 NB_LINES = 10500
 ALWAYS_CHANGE_LINES = 500
 OTHER_CHANGES = 300
 
+
 def nextcontent(previous_content):
     """utility to produce a new file content from the previous one"""
     return hashlib.md5(previous_content).hexdigest()
 
+
 def filecontent(iteridx, oldcontent):
     """generate a new file content
 
@@ -72,6 +74,7 @@
             to_write = oldcontent[idx]
         yield to_write
 
+
 def updatefile(filename, idx):
     """update <filename> to be at appropriate content for iteration <idx>"""
     existing = None
@@ -82,6 +85,7 @@
         for line in filecontent(idx, existing):
             target.write(line)
 
+
 def hg(command, *args):
     """call a mercurial command with appropriate config and argument"""
     env = os.environ.copy()
@@ -101,6 +105,7 @@
     env['HGRCPATH'] = ''
     return subprocess.check_call(full_cmd, env=env)
 
+
 def run(target):
     tmpdir = tempfile.mkdtemp(prefix='tmp-hg-test-big-file-bundle-')
     try:
@@ -131,8 +136,8 @@
         shutil.rmtree(tmpdir)
     return 0
 
+
 if __name__ == '__main__':
     orig = os.path.realpath(os.path.dirname(sys.argv[0]))
     target = os.path.join(orig, os.pardir, 'cache', BUNDLE_NAME)
     sys.exit(run(target))
-