diff --git a/src/python/code/gnoll/__main__.py b/src/python/code/gnoll/__main__.py
index 7ae6b78b5..c63ac4dc7 100644
--- a/src/python/code/gnoll/__main__.py
+++ b/src/python/code/gnoll/__main__.py
@@ -1,7 +1,8 @@
 """Roll some dice with GNOLL."""
 
-import sys
 import argparse
+import sys
+
 import gnoll
 
 
@@ -9,73 +10,59 @@ def parse_cmdline_args(args):
     """Extract values from the commandline
     @param args - the arguments from the commandline (excluding the python3 call)
     """
-    p = argparse.ArgumentParser(
-        description=__doc__,
-        usage='python3 -m gnoll [options] EXPR',
-        add_help=False)
+    p = argparse.ArgumentParser(description=__doc__,
+                                usage="python3 -m gnoll [options] EXPR",
+                                add_help=False)
 
     p.add_argument(
-        'EXPR',
-        nargs='+',
-        help='a dice expression to evaluate'
-             '(multiple arguments will be joined with spaces)'
+        "EXPR",
+        nargs="+",
+        help="a dice expression to evaluate"
+        "(multiple arguments will be joined with spaces)",
     )
 
-    g = p.add_argument_group('main options')
-    g.add_argument(
-        '-h',
-        '--help',
-        action='help',
-        help='show this help message and exit'
-    )
+    g = p.add_argument_group("main options")
+    g.add_argument("-h",
+                   "--help",
+                   action="help",
+                   help="show this help message and exit")
     g.add_argument(
-        '-b',
-        '--breakdown',
-        action='store_true',
-        help='show a breakdown into individual dice'
+        "-b",
+        "--breakdown",
+        action="store_true",
+        help="show a breakdown into individual dice",
     )
     g.add_argument(
-        '-n',
-        '--times',
-        metavar='N',
+        "-n",
+        "--times",
+        metavar="N",
         type=int,
         default=1,
-        help='execute the entire expression N times'
-    )
-    g.add_argument(
-        '--no-builtins',
-        action='store_true',
-        help='disable built-in macros'
+        help="execute the entire expression N times",
     )
+    g.add_argument("--no-builtins",
+                   action="store_true",
+                   help="disable built-in macros")
 
-    g = p.add_argument_group('debugging options')
+    g = p.add_argument_group("debugging options")
+    g.add_argument("-v",
+                   "--verbose",
+                   action="store_true",
+                   help="enable verbosity")
     g.add_argument(
-        '-v',
-        '--verbose',
-        action='store_true',
-        help='enable verbosity'
-    )
-    g.add_argument(
-        '--keep-temp-file',
-        action='store_true',
-        help="don't delete the created temporary file"
-    )
-    g.add_argument(
-        '--mock',
-        metavar='TYPE',
-        type=int,
-        help='mocking type'
-    )
-    g.add_argument(
-        '--mock-const',
-        metavar='N',
-        type=int,
-        default=3,
-        help='mocking constant'
+        "--keep-temp-file",
+        action="store_true",
+        help="don't delete the created temporary file",
     )
+    g.add_argument("--mock", metavar="TYPE", type=int, help="mocking type")
+    g.add_argument("--mock-const",
+                   metavar="N",
+                   type=int,
+                   default=3,
+                   help="mocking constant")
 
     a = p.parse_args(args)
-    a.EXPR = ' '.join(a.EXPR)
+    a.EXPR = " ".join(a.EXPR)
     return a
 
 
@@ -88,11 +75,10 @@ def main(EXPR, times, no_builtins, **kwargs):
     @param **kwargs - other key word arguments to be passed to gnoll.roll
     """
     for _ in range(times):
-        _, [[result]], breakdown = gnoll.roll(
-            EXPR,
-            builtins=not no_builtins,
-            **kwargs)
-        yield (breakdown[0], '-->', result) if breakdown else (result,)
+        _, [[result]], breakdown = gnoll.roll(EXPR,
+                                              builtins=not no_builtins,
+                                              **kwargs)
+        yield (breakdown[0], "-->", result) if breakdown else (result, )
 
 
 def main_with_args(args):
@@ -102,6 +88,6 @@ def main_with_args(args):
     yield from main(**vars(parse_cmdline_args(args)))
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     for line in main_with_args(sys.argv[1:]):
         print(*line)
diff --git a/tests/python/test_cli.py b/tests/python/test_cli.py
index b5c4473f2..5833c3863 100644
--- a/tests/python/test_cli.py
+++ b/tests/python/test_cli.py
@@ -1,20 +1,19 @@
 import gnoll.__main__
 
-
 m = lambda *x: list(gnoll.__main__.main_with_args(x))
 
 
 def test_cli():
-
-    [[r]] = m('1d4')
+    [[r]] = m("1d4")
     assert isinstance(r, int)
 
-    [[(die1, die2), a, r]] = m('2d4', '--breakdown')
+    [[(die1, die2), a, r]] = m("2d4", "--breakdown")
     assert all((isinstance(x, int) for x in [die1, die2, r]))
-    assert a == '-->'
+    assert a == "-->"
 
-    executions = m('4d6kh3', '+', '1', '--breakdown', '--times', '6', '--no-builtins')
+    executions = m("4d6kh3", "+", "1", "--breakdown", "--times", "6",
+                   "--no-builtins")
     assert len(executions) == 6
     for (die1, die2, die3, die4), a, r in executions:
         assert all((isinstance(x, int) for x in [die1, die2, die3, die4, r]))
-        assert a == '-->'
+        assert a == "-->"