Format files with black

- Format all files with black
- Update tox.ini flake8 arguments to be compatible
- Add black to requirements-extra.txt
- Reduce ignored flake8 rules and fix a few violations

core/pe/cache.py

@@ -4,7 +4,8 @@
 # which should be included with this package. The terms are also available at
 # http://www.gnu.org/licenses/gpl-3.0.html
 
-from ._cache import string_to_colors # noqa
+from ._cache import string_to_colors  # noqa
+
 
 def colors_to_string(colors):
     """Transform the 3 sized tuples 'colors' into a hex string.
@@ -12,7 +13,8 @@ def colors_to_string(colors):
     [(0,100,255)] --> 0064ff
     [(1,2,3),(4,5,6)] --> 010203040506
     """
-    return ''.join('%02x%02x%02x' % (r, g, b) for r, g, b in colors)
+    return "".join("%02x%02x%02x" % (r, g, b) for r, g, b in colors)
+
 
 # This function is an important bottleneck of dupeGuru PE. It has been converted to C.
 # def string_to_colors(s):
@@ -23,4 +25,3 @@ def colors_to_string(colors):
 #         number = int(s[i:i+6], 16)
 #         result.append((number >> 16, (number >> 8) & 0xff, number & 0xff))
 #     return result
-