diff --git a/scripts/test_runner.py b/scripts/test_runner.py
index b50ae07..fa95c68 100755
--- a/scripts/test_runner.py
+++ b/scripts/test_runner.py
@@ -13,20 +13,20 @@
 parser = argparse.ArgumentParser(
     description="Run a springbok test on an simulator.")
 
-parser.add_argument('simulator',
-                    help='Select a simulator',
-                    choices=['renode', 'qemu', 'spike'])
-parser.add_argument('elf',
-                    help='Elf to execute on a simulator')
-parser.add_argument('--renode-path',
+parser.add_argument("simulator",
+                    help="Select a simulator",
+                    choices=["renode", "qemu", "spike"])
+parser.add_argument("elf",
+                    help="Elf to execute on a simulator")
+parser.add_argument("--renode-path",
                     help="Path to renode simulator")
 parser.add_argument("--trace-output",
                     help="Path to trace output file")
-parser.add_argument('--qemu-path',
+parser.add_argument("--qemu-path",
                     help="Path to qemu simulator")
-parser.add_argument('--spike-path',
+parser.add_argument("--spike-path",
                     help="Path to spike simulator")
-parser.add_argument('--timeout', type=int,
+parser.add_argument("--timeout", type=int,
                     help="Timeout for test", default=1000)
 parser.add_argument("--quick_test",
                     help="allow quickest test time", action="store_true")
@@ -47,7 +47,7 @@
 
     def run(self, timeout=1000):
         """ Run the simulation command and quit the simulation."""
-        self.child = pexpect.spawn(self.simulator_cmd, encoding='utf-8')
+        self.child = pexpect.spawn(self.simulator_cmd, encoding="utf-8")
         self.child.logfile = self.buffer
         self.child.expect(self.termination_strings, timeout=timeout)
         self.child.send("\nq\n")
@@ -69,7 +69,7 @@
     """ Renode Simulation """
     def __init__(self, path, elf):
         # Get the ROOTDIR path if it exists
-        self.rootdir = os.environ.get('ROOTDIR', default=None)
+        self.rootdir = os.environ.get("ROOTDIR", default=None)
         if self.rootdir is None:
             parser.error("ROOTDIR environment variable not set.")
         renode_script = """
@@ -97,9 +97,9 @@
         self.renode_script = renode_script % self.script_params
         self.renode_args = [
             "%s" % path,
-            '--disable-xwt',
-            ' --console',
-            '--plain',
+            "--disable-xwt",
+            " --console",
+            "--plain",
         ]
         self.renode_simulator_cmd = " ".join(self.renode_args)
         super().__init__(self.renode_simulator_cmd)
@@ -107,7 +107,7 @@
     def run(self, timeout=120):
         file_desc, script_path = tempfile.mkstemp(suffix=".resc")
         try:
-            with os.fdopen(file_desc, 'w') as tmp:
+            with os.fdopen(file_desc, "w") as tmp:
                 tmp.write(self.renode_script)
                 tmp.flush()
             self.simulator_cmd += " %s" % script_path