Fix lint errors

IPython/core/display.py

@@ -801,9 +801,20 b' class Image(DisplayObject):'
         _FMT_GIF: 'image/gif',
     }
 
-    def __init__(self, data=None, url=None, filename=None, format=None,
-                 embed=None, width=None, height=None, retina=False,
-                 unconfined=False, metadata=None, alt=None):
+    def __init__(
+        self,
+        data=None,
+        url=None,
+        filename=None,
+        format=None,
+        embed=None,
+        width=None,
+        height=None,
+        retina=False,
+        unconfined=False,
+        metadata=None,
+        alt=None,
+    ):
         """Create a PNG/JPEG/GIF image object given raw data.
 
         When this object is returned by an input cell or passed to the
@@ -937,8 +948,8 b' class Image(DisplayObject):'
         if self.height is None and self.metadata.get('height', {}):
             self.height = metadata['height']
 
-        if self.alt is None and self.metadata.get('alt', {}):
-            self.alt = metadata['alt']
+        if self.alt is None and self.metadata.get("alt", {}):
+            self.alt = metadata["alt"]
 
         if retina:
             self._retina_shape()
@@ -969,7 +980,7 b' class Image(DisplayObject):'
 
     def _repr_html_(self):
         if not self.embed:
-            width = height = klass = alt = ''
+            width = height = klass = alt = ""
             if self.width:
                 width = ' width="%d"' % self.width
             if self.height:
@@ -978,7 +989,7 b' class Image(DisplayObject):'
                 klass = ' class="unconfined"'
             if self.alt:
                 alt = ' alt="%s"' % html.escape(self.alt)
-            return u'<img src="{url}"{width}{height}{klass}{alt}/>'.format(
+            return '<img src="{url}"{width}{height}{klass}{alt}/>'.format(
                 url=self.url,
                 width=width,
                 height=height,
@@ -1017,7 +1028,7 b' class Image(DisplayObject):'
         if self.unconfined:
             md['unconfined'] = self.unconfined
         if self.alt:
-            md['alt'] = self.alt
+            md["alt"] = self.alt
         if md or always_both:
             return b64_data, md
         else:

IPython/core/tests/test_display.py

@@ -94,9 +94,9 b' def test_embed_svg_url():'
 
         if args[0] == url:
             return MockResponse(svg_data)
-        elif args[0] == url + 'z':
-            ret= MockResponse(gzip_svg)
-            ret.headers['content-encoding']= 'gzip'
+        elif args[0] == url + "z":
+            ret = MockResponse(gzip_svg)
+            ret.headers["content-encoding"] = "gzip"
             return ret
         return MockResponse(None)
 
@@ -459,19 +459,24 b' def test_display_handle():'
 
 def test_image_alt_tag():
     """Simple test for display.Image(args, alt=x,)"""
-    thisurl = 'http://example.com/image.png'
-    img = display.Image(url=thisurl, alt='an image')
+    thisurl = "http://example.com/image.png"
+    img = display.Image(url=thisurl, alt="an image")
     nt.assert_equal(u'<img src="%s" alt="an image"/>' % (thisurl), img._repr_html_())
-    img = display.Image(url=thisurl, unconfined=True, alt='an image')
-    nt.assert_equal(u'<img src="%s" class="unconfined" alt="an image"/>' % (thisurl), img._repr_html_())
+    img = display.Image(url=thisurl, unconfined=True, alt="an image")
+    nt.assert_equal(
+        u'<img src="%s" class="unconfined" alt="an image"/>' % (thisurl),
+        img._repr_html_(),
+    )
     img = display.Image(url=thisurl, alt='>"& <')
-    nt.assert_equal(u'<img src="%s" alt="&gt;&quot;&amp; &lt;"/>' % (thisurl), img._repr_html_())
+    nt.assert_equal(
+        u'<img src="%s" alt="&gt;&quot;&amp; &lt;"/>' % (thisurl), img._repr_html_()
+    )
 
-    img = display.Image(url=thisurl, metadata={'alt':'an image'})
-    nt.assert_equal(img.alt, 'an image')
+    img = display.Image(url=thisurl, metadata={"alt": "an image"})
+    nt.assert_equal(img.alt, "an image")
 
     here = os.path.dirname(__file__)
-    img = display.Image(os.path.join(here, "2x2.png"), alt='an image')
-    nt.assert_equal(img.alt, 'an image')
+    img = display.Image(os.path.join(here, "2x2.png"), alt="an image")
+    nt.assert_equal(img.alt, "an image")
     _, md = img._repr_png_()
-    nt.assert_equal(md['alt'], 'an image')
+    nt.assert_equal(md["alt"], "an image")