pipeline env: added black for code formatting

Pipfile

@@ -10,6 +10,9 @@ freesurfer-volume-reader = {editable = true, path = "."}
 numpy = "<1.19.0"
 
 [dev-packages]
+# black requires python>=3.6
+# https://github.com/psf/black/commit/e74117f172e29e8a980e2c9de929ad50d3769150#diff-2eeaed663bd0d25b7e608891384b7298R51
+black = {version = "==19.10b0", markers="python_version >= '3.6'"}
 pylint = "*"
 pytest = "*"
 pytest-cov = "*"

Pipfile.lock

@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "b1ab9031e0f908588df278ac271280c98464e94a32fbbc34632ba5b22659cd24"
+            "sha256": "e251c5ec71c137fedb9cca4edcc6a742c835c3eea75e4e9fe654f1dc50da6add"
         },
         "pipfile-spec": 6,
         "requires": {
@@ -94,6 +94,13 @@
         }
     },
     "develop": {
+        "appdirs": {
+            "hashes": [
+                "sha256:7d5d0167b2b1ba821647616af46a749d1c653740dd0d2415100fe26e27afdf41",
+                "sha256:a841dacd6b99318a741b166adb07e19ee71a274450e68237b4650ca1055ab128"
+            ],
+            "version": "==1.4.4"
+        },
         "astroid": {
             "hashes": [
                 "sha256:2f4078c2a41bf377eea06d71c9d2ba4eb8f6b1af2135bec27bbbb7d8f12bb703",
@@ -108,6 +115,22 @@
             ],
             "version": "==19.3.0"
         },
+        "black": {
+            "hashes": [
+                "sha256:1b30e59be925fafc1ee4565e5e08abef6b03fe455102883820fe5ee2e4734e0b",
+                "sha256:c2edb73a08e9e0e6f65a0e6af18b059b8b1cdd5bef997d7a0b181df93dc81539"
+            ],
+            "index": "pypi",
+            "markers": "python_version >= '3.6'",
+            "version": "==19.10b0"
+        },
+        "click": {
+            "hashes": [
+                "sha256:d2b5255c7c6349bc1bd1e59e08cd12acbbd63ce649f2588755783aa94dfb6b1a",
+                "sha256:dacca89f4bfadd5de3d7489b7c8a566eee0d3676333fbb50030263894c38c0dc"
+            ],
+            "version": "==7.1.2"
+        },
         "coverage": {
             "hashes": [
                 "sha256:0fc4e0d91350d6f43ef6a61f64a48e917637e1dcfcba4b4b7d543c628ef82c2d",
@@ -219,6 +242,13 @@
             "markers": "python_version < '3.6'",
             "version": "==2.3.5"
         },
+        "pathspec": {
+            "hashes": [
+                "sha256:7d91249d21749788d07a2d0f94147accd8f845507400749ea19c1ec9054a12b0",
+                "sha256:da45173eb3a6f2a5a487efba21f050af2b41948be6ab52b6a1e3ff22bb8b7061"
+            ],
+            "version": "==0.8.0"
+        },
         "pluggy": {
             "hashes": [
                 "sha256:15b2acde666561e1298d71b523007ed7364de07029219b604cf808bfa1c765b0",
@@ -272,6 +302,32 @@
             "index": "pypi",
             "version": "==1.4.1"
         },
+        "regex": {
+            "hashes": [
+                "sha256:08997a37b221a3e27d68ffb601e45abfb0093d39ee770e4257bd2f5115e8cb0a",
+                "sha256:112e34adf95e45158c597feea65d06a8124898bdeac975c9087fe71b572bd938",
+                "sha256:1700419d8a18c26ff396b3b06ace315b5f2a6e780dad387e4c48717a12a22c29",
+                "sha256:2f6f211633ee8d3f7706953e9d3edc7ce63a1d6aad0be5dcee1ece127eea13ae",
+                "sha256:52e1b4bef02f4040b2fd547357a170fc1146e60ab310cdbdd098db86e929b387",
+                "sha256:55b4c25cbb3b29f8d5e63aeed27b49fa0f8476b0d4e1b3171d85db891938cc3a",
+                "sha256:5aaa5928b039ae440d775acea11d01e42ff26e1561c0ffcd3d805750973c6baf",
+                "sha256:654cb773b2792e50151f0e22be0f2b6e1c3a04c5328ff1d9d59c0398d37ef610",
+                "sha256:690f858d9a94d903cf5cada62ce069b5d93b313d7d05456dbcd99420856562d9",
+                "sha256:6ad8663c17db4c5ef438141f99e291c4d4edfeaacc0ce28b5bba2b0bf273d9b5",
+                "sha256:89cda1a5d3e33ec9e231ece7307afc101b5217523d55ef4dc7fb2abd6de71ba3",
+                "sha256:92d8a043a4241a710c1cf7593f5577fbb832cf6c3a00ff3fc1ff2052aff5dd89",
+                "sha256:95fa7726d073c87141f7bbfb04c284901f8328e2d430eeb71b8ffdd5742a5ded",
+                "sha256:97712e0d0af05febd8ab63d2ef0ab2d0cd9deddf4476f7aa153f76feef4b2754",
+                "sha256:b2ba0f78b3ef375114856cbdaa30559914d081c416b431f2437f83ce4f8b7f2f",
+                "sha256:bae83f2a56ab30d5353b47f9b2a33e4aac4de9401fb582b55c42b132a8ac3868",
+                "sha256:c78e66a922de1c95a208e4ec02e2e5cf0bb83a36ceececc10a72841e53fbf2bd",
+                "sha256:cf59bbf282b627130f5ba68b7fa3abdb96372b24b66bdf72a4920e8153fc7910",
+                "sha256:e3cdc9423808f7e1bb9c2e0bdb1c9dc37b0607b30d646ff6faf0d4e41ee8fee3",
+                "sha256:e9b64e609d37438f7d6e68c2546d2cb8062f3adb27e6336bc129b51be20773ac",
+                "sha256:fbff901c54c22425a5b809b914a3bfaf4b9570eee0e5ce8186ac71eb2025191c"
+            ],
+            "version": "==2020.6.8"
+        },
         "six": {
             "hashes": [
                 "sha256:30639c035cdb23534cd4aa2dd52c3bf48f06e5f4a941509c8bafd8ce11080259",
@@ -286,6 +342,32 @@
             ],
             "version": "==0.10.1"
         },
+        "typed-ast": {
+            "hashes": [
+                "sha256:0666aa36131496aed8f7be0410ff974562ab7eeac11ef351def9ea6fa28f6355",
+                "sha256:0c2c07682d61a629b68433afb159376e24e5b2fd4641d35424e462169c0a7919",
+                "sha256:249862707802d40f7f29f6e1aad8d84b5aa9e44552d2cc17384b209f091276aa",
+                "sha256:24995c843eb0ad11a4527b026b4dde3da70e1f2d8806c99b7b4a7cf491612652",
+                "sha256:269151951236b0f9a6f04015a9004084a5ab0d5f19b57de779f908621e7d8b75",
+                "sha256:4083861b0aa07990b619bd7ddc365eb7fa4b817e99cf5f8d9cf21a42780f6e01",
+                "sha256:498b0f36cc7054c1fead3d7fc59d2150f4d5c6c56ba7fb150c013fbc683a8d2d",
+                "sha256:4e3e5da80ccbebfff202a67bf900d081906c358ccc3d5e3c8aea42fdfdfd51c1",
+                "sha256:6daac9731f172c2a22ade6ed0c00197ee7cc1221aa84cfdf9c31defeb059a907",
+                "sha256:715ff2f2df46121071622063fc7543d9b1fd19ebfc4f5c8895af64a77a8c852c",
+                "sha256:73d785a950fc82dd2a25897d525d003f6378d1cb23ab305578394694202a58c3",
+                "sha256:8c8aaad94455178e3187ab22c8b01a3837f8ee50e09cf31f1ba129eb293ec30b",
+                "sha256:8ce678dbaf790dbdb3eba24056d5364fb45944f33553dd5869b7580cdbb83614",
+                "sha256:aaee9905aee35ba5905cfb3c62f3e83b3bec7b39413f0a7f19be4e547ea01ebb",
+                "sha256:bcd3b13b56ea479b3650b82cabd6b5343a625b0ced5429e4ccad28a8973f301b",
+                "sha256:c9e348e02e4d2b4a8b2eedb48210430658df6951fa484e59de33ff773fbd4b41",
+                "sha256:d205b1b46085271b4e15f670058ce182bd1199e56b317bf2ec004b6a44f911f6",
+                "sha256:d43943ef777f9a1c42bf4e552ba23ac77a6351de620aa9acf64ad54933ad4d34",
+                "sha256:d5d33e9e7af3b34a40dc05f498939f0ebf187f07c385fd58d591c533ad8562fe",
+                "sha256:fc0fea399acb12edbf8a628ba8d2312f583bdbdb3335635db062fa98cf71fca4",
+                "sha256:fe460b922ec15dd205595c9b5b99e2f056fd98ae8f9f56b888e7a17dc2b757e7"
+            ],
+            "version": "==1.4.1"
+        },
         "wcwidth": {
             "hashes": [
                 "sha256:beb4802a9cebb9144e99086eff703a642a13d6a0052920003a230f3294bbe784",