[V3] Update black version and reformat (#1745)

* Update black version and reformat

* Pin black in extras_require

Pipfile.lock

@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "d340e4a19777736703970e45766d05d67b973db38b87382b6ef8696cb53abb60"
+            "sha256": "b6f739015def0fc7efb2b9aab7b0cc7e21d88e56b9b73f8611669d8c0814bc64"
         },
         "pipfile-spec": 6,
         "requires": {},
@@ -248,19 +248,18 @@
         },
         "babel": {
             "hashes": [
-                "sha256:8ce4cb6fdd4393edd323227cba3a077bceb2a6ce5201c902c65e730046f41f14",
-                "sha256:ad209a68d7162c4cff4b29cdebe3dec4cef75492df501b0049a9433c96ce6f80"
+                "sha256:6778d85147d5d85345c14a26aada5e478ab04e39b078b0745ee6870c2b5cf669",
+                "sha256:8cba50f48c529ca3fa18cf81fa9403be176d374ac4d60738b839122dfaaa3d23"
             ],
-            "version": "==2.5.3"
+            "version": "==2.6.0"
         },
         "black": {
             "hashes": [
-                "sha256:4fec2566f9fbbd4a58de50a168cbe3ab952713530410d227e82e4c65d1fad946",
-                "sha256:5fec0f25486046b9edb97961c946412ced96021247dd1a60ecd9f0567b68b030"
+                "sha256:c956857a831e508e75f0dc754b86982bad98d95c96aae39c20749209b3958ad7",
+                "sha256:fa8d4b58aeb454443d4ef02c9daa615cd9a241f0cbe5f2b38b5965209d26dd1c"
             ],
             "index": "pypi",
-            "markers": "python_version >= '3.6'",
-            "version": "==18.5b0"
+            "version": "==18.5b1"
         },
         "certifi": {
             "hashes": [
@@ -413,11 +412,11 @@
         },
         "sphinx": {
             "hashes": [
-                "sha256:2e7ad92e96eff1b2006cf9f0cdb2743dacbae63755458594e9e8238b0c3dc60b",
-                "sha256:e9b1a75a3eae05dded19c80eb17325be675e0698975baae976df603b6ed1eb10"
+                "sha256:85f7e32c8ef07f4ba5aeca728e0f7717bef0789fba8458b8d9c5c294cad134f3",
+                "sha256:d45480a229edf70d84ca9fae3784162b1bc75ee47e480ffe04a4b7f21a95d76d"
             ],
             "index": "pypi",
-            "version": "==1.7.4"
+            "version": "==1.7.5"
         },
         "sphinx-rtd-theme": {
             "hashes": [