diff --git a/src/PIL/ImageOps.py b/src/PIL/ImageOps.py
index b513776a4..39938205b 100644
--- a/src/PIL/ImageOps.py
+++ b/src/PIL/ImageOps.py
@@ -521,10 +521,10 @@ def invert(image):
     :return: An image.
     """
     # Special case for 1-bit images using python translate() method
-    if image.mode == '1':
-        lut = bytearray(range(255,-1,-1))
-        return Image.frombuffer('1',image.size,image.tobytes().translate(lut))
-    
+    if image.mode == "1":
+        lut = bytearray(range(255, -1, -1))
+        return Image.frombuffer("1", image.size, image.tobytes().translate(lut))
+
     lut = []
     for i in range(256):
         lut.append(255 - i)