diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d55af7f..04c918b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,6 +8,8 @@ jobs:
     strategy:
       matrix:
         python:
+          - '3.6'
+          - '3.7'
           - '3.8'
           - '3.9'
           - '3.10'
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 7184208..4497fd5 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -1,3 +1,5 @@
+default_language_version:
+  python: python3
 repos:
   - repo: local
     hooks:
diff --git a/Pipfile b/Pipfile
index a34765f..6d33de4 100644
--- a/Pipfile
+++ b/Pipfile
@@ -8,6 +8,7 @@ pytest = "*"
 black = "*"
 twine = "*"
 pre-commit = "*"
+typing-extensions = "*"
 
 [packages]
 
diff --git a/Pipfile.lock b/Pipfile.lock
index e3cc413..5219241 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -1,7 +1,7 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "83d4fa5d222edd702b818587bdc3eab2d33bc8c4a3b705d186f6da245e298927"
+            "sha256": "96eba5e6f91e969552a41c0abcad320581d70f5008aa7404b58e731db70db59b"
         },
         "pipfile-spec": 6,
         "requires": {},
@@ -15,13 +15,6 @@
     },
     "default": {},
     "develop": {
-        "appdirs": {
-            "hashes": [
-                "sha256:7d5d0167b2b1ba821647616af46a749d1c653740dd0d2415100fe26e27afdf41",
-                "sha256:a841dacd6b99318a741b166adb07e19ee71a274450e68237b4650ca1055ab128"
-            ],
-            "version": "==1.4.4"
-        },
         "attrs": {
             "hashes": [
                 "sha256:149e90d6d8ac20db7a955ad60cf0e6881a3f20d37096140088356da6c716b0b1",
@@ -30,52 +23,60 @@
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
             "version": "==21.2.0"
         },
+        "backports.entry-points-selectable": {
+            "hashes": [
+                "sha256:7fceed9532a7aa2bd888654a7314f864a3c16a4e710b34a58cfc0f08114c663b",
+                "sha256:914b21a479fde881635f7af5adc7f6e38d6b274be32269070c53b698c60d5386"
+            ],
+            "markers": "python_version >= '2.7'",
+            "version": "==1.1.1"
+        },
         "black": {
             "hashes": [
-                "sha256:dc132348a88d103016726fe360cb9ede02cecf99b76e3660ce6c596be132ce04",
-                "sha256:dfb8c5a069012b2ab1e972e7b908f5fb42b6bbabcba0a788b86dc05067c7d9c7"
+                "sha256:6eb7448da9143ee65b856a5f3676b7dda98ad9abe0f87fce8c59291f15e82a5b",
+                "sha256:a9952229092e325fe5f3dae56d81f639b23f7131eb840781947e4b2886030f33"
             ],
             "index": "pypi",
-            "version": "==21.6b0"
+            "version": "==21.10b0"
         },
         "bleach": {
             "hashes": [
-                "sha256:6123ddc1052673e52bab52cdc955bcb57a015264a1c57d37bea2f6b817af0125",
-                "sha256:98b3170739e5e83dd9dc19633f074727ad848cbedb6026708c8ac2d3b697a433"
+                "sha256:0900d8b37eba61a802ee40ac0061f8c2b5dee29c1927dd1d233e075ebf5a71da",
+                "sha256:4d2651ab93271d1129ac9cbc679f524565cc8a1b791909c4a51eac4446a15994"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
-            "version": "==3.3.0"
+            "markers": "python_version >= '3.6'",
+            "version": "==4.1.0"
         },
         "certifi": {
             "hashes": [
-                "sha256:2bbf76fd432960138b3ef6dda3dde0544f27cbf8546c458e60baf371917ba9ee",
-                "sha256:50b1e4f8446b06f41be7dd6338db18e0990601dce795c2b1686458aa7e8fa7d8"
+                "sha256:78884e7c1d4b00ce3cea67b44566851c4343c120abd683433ce934a68ea58872",
+                "sha256:d62a0163eb4c2344ac042ab2bdf75399a71a2d8c7d47eac2e2ee91b9d6339569"
             ],
-            "version": "==2021.5.30"
+            "version": "==2021.10.8"
         },
         "cfgv": {
             "hashes": [
-                "sha256:9e600479b3b99e8af981ecdfc80a0296104ee610cab48a5ae4ffd0b668650eb1",
-                "sha256:b449c9c6118fe8cca7fa5e00b9ec60ba08145d281d52164230a69211c5d597a1"
+                "sha256:c6a0883f3917a037485059700b9e75da2464e6c27051014ad85ba6aaa5884426",
+                "sha256:f5a830efb9ce7a445376bb66ec94c638a9787422f96264c98edc6bdeed8ab736"
             ],
             "markers": "python_full_version >= '3.6.1'",
-            "version": "==3.3.0"
+            "version": "==3.3.1"
         },
-        "chardet": {
+        "charset-normalizer": {
             "hashes": [
-                "sha256:0d6f53a15db4120f2b08c94f11e7d93d2c911ee118b6b30a04ec3ee8310179fa",
-                "sha256:f864054d66fd9118f2e67044ac8981a54775ec5b67aed0441892edb553d21da5"
+                "sha256:e019de665e2bcf9c2b64e2e5aa025fa991da8720daa3c1138cadd2fd1856aed0",
+                "sha256:f7af805c321bfa1ce6714c51f254e0d5bb5e5834039bc17db7ebe3a4cec9492b"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
-            "version": "==4.0.0"
+            "markers": "python_version >= '3'",
+            "version": "==2.0.7"
         },
         "click": {
             "hashes": [
-                "sha256:8c04c11192119b1ef78ea049e0a6f0463e4c48ef00a30160c704337586f3ad7a",
-                "sha256:fba402a4a47334742d782209a7c79bc448911afe1149d07bdabdf480b3e2f4b6"
+                "sha256:353f466495adaeb40b6b5f592f9f91cb22372351c84caeb068132442a4518ef3",
+                "sha256:410e932b050f5eed773c4cda94de75971c89cdb3155a72a0831139a79e5ecb5b"
             ],
             "markers": "python_version >= '3.6'",
-            "version": "==8.0.1"
+            "version": "==8.0.3"
         },
         "colorama": {
             "hashes": [
@@ -85,51 +86,68 @@
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
             "version": "==0.4.4"
         },
+        "dataclasses": {
+            "hashes": [
+                "sha256:0201d89fa866f68c8ebd9d08ee6ff50c0b255f8ec63a71c16fda7af82bb887bf",
+                "sha256:8479067f342acf957dc82ec415d355ab5edb7e7646b90dc6e2fd1d96ad084c97"
+            ],
+            "markers": "python_version < '3.7'",
+            "version": "==0.8"
+        },
         "distlib": {
             "hashes": [
-                "sha256:106fef6dc37dd8c0e2c0a60d3fca3e77460a48907f335fa28420463a6f799736",
-                "sha256:23e223426b28491b1ced97dc3bbe183027419dfc7982b4fa2f05d5f3ff10711c"
+                "sha256:c8b54e8454e5bf6237cc84c20e8264c3e991e824ef27e8f1e81049867d861e31",
+                "sha256:d982d0751ff6eaaab5e2ec8e691d949ee80eddf01a62eaa96ddb11531fe16b05"
             ],
-            "version": "==0.3.2"
+            "version": "==0.3.3"
         },
         "docutils": {
             "hashes": [
-                "sha256:686577d2e4c32380bb50cbb22f575ed742d58168cee37e99117a854bcd88f125",
-                "sha256:cf316c8370a737a022b72b56874f6602acf974a37a9fba42ec2876387549fc61"
+                "sha256:a31688b2ea858517fa54293e5d5df06fbb875fb1f7e4c64529271b77781ca8fc",
+                "sha256:c1d5dab2b11d16397406a282e53953fe495a46d69ae329f55aa98a5c4e3c5fbb"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
-            "version": "==0.17.1"
+            "version": "==0.18"
         },
         "filelock": {
             "hashes": [
-                "sha256:18d82244ee114f543149c66a6e0c14e9c4f8a1044b5cdaadd0f82159d6a6ff59",
-                "sha256:929b7d63ec5b7d6b71b0fa5ac14e030b3f70b75747cef1b10da9b879fef15836"
+                "sha256:7afc856f74fa7006a289fd10fa840e1eebd8bbff6bffb69c26c54a0512ea8cf8",
+                "sha256:bb2a1c717df74c48a2d00ed625e5a66f8572a3a30baacb7657add1d7bac4097b"
             ],
-            "version": "==3.0.12"
+            "markers": "python_version >= '3.6'",
+            "version": "==3.3.2"
         },
         "identify": {
             "hashes": [
-                "sha256:18d0c531ee3dbc112fa6181f34faa179de3f57ea57ae2899754f16a7e0ff6421",
-                "sha256:5b41f71471bc738e7b586308c3fca172f78940195cb3bf6734c1e66fdac49306"
+                "sha256:6f0368ba0f21c199645a331beb7425d5374376e71bc149e9cb55e45cb45f832d",
+                "sha256:ba945bddb4322394afcf3f703fa68eda08a6acc0f99d9573eb2be940aa7b9bba"
             ],
             "markers": "python_full_version >= '3.6.1'",
-            "version": "==2.2.10"
+            "version": "==2.3.5"
         },
         "idna": {
             "hashes": [
-                "sha256:b307872f855b18632ce0c21c5e45be78c0ea7ae4c15c828c20788b26921eb3f6",
-                "sha256:b97d804b1e9b523befed77c48dacec60e6dcb0b5391d57af6a65a312a90648c0"
+                "sha256:84d9dd047ffa80596e0f246e2eab0b391788b0503584e8945f2368256d2735ff",
+                "sha256:9d643ff0a55b762d5cdb124b8eaa99c66322e2157b69160bc32796e824360e6d"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==2.10"
+            "markers": "python_version >= '3'",
+            "version": "==3.3"
         },
         "importlib-metadata": {
             "hashes": [
-                "sha256:079ada16b7fc30dfbb5d13399a5113110dab1aa7c2bc62f66af75f0b717c8cac",
-                "sha256:9f55f560e116f8643ecf2922d9cd3e1c7e8d52e683178fecd9d08f6aa357e11e"
+                "sha256:53ccfd5c134223e497627b9815d5030edf77d2ed573922f7a0b8f8bb81a1c100",
+                "sha256:75bdec14c397f528724c1bfd9709d660b33a4d2e77387a3358f20b848bb5e5fb"
             ],
-            "markers": "python_version >= '3.6'",
-            "version": "==4.6.1"
+            "markers": "python_version < '3.8'",
+            "version": "==4.8.2"
+        },
+        "importlib-resources": {
+            "hashes": [
+                "sha256:33a95faed5fc19b4bc16b29a6eeae248a3fe69dd55d4d229d2b480e23eeaad45",
+                "sha256:d756e2f85dd4de2ba89be0b21dba2a3bbec2e871a42a3a16719258a11f87506b"
+            ],
+            "markers": "python_version < '3.7'",
+            "version": "==5.4.0"
         },
         "iniconfig": {
             "hashes": [
@@ -140,11 +158,11 @@
         },
         "keyring": {
             "hashes": [
-                "sha256:045703609dd3fccfcdb27da201684278823b72af515aedec1a8515719a038cb8",
-                "sha256:8f607d7d1cc502c43a932a275a56fe47db50271904513a379d39df1af277ac48"
+                "sha256:6334aee6073db2fb1f30892697b1730105b5e9a77ce7e61fca6b435225493efe",
+                "sha256:bd2145a237ed70c8ce72978b497619ddfcae640b6dcf494402d5143e37755c6e"
             ],
             "markers": "python_version >= '3.6'",
-            "version": "==23.0.1"
+            "version": "==23.2.1"
         },
         "mypy-extensions": {
             "hashes": [
@@ -162,57 +180,65 @@
         },
         "packaging": {
             "hashes": [
-                "sha256:7dc96269f53a4ccec5c0670940a4281106dd0bb343f47b7471f779df49c2fbe7",
-                "sha256:c86254f9220d55e31cc94d69bade760f0847da8000def4dfe1c6b872fd14ff14"
+                "sha256:096d689d78ca690e4cd8a89568ba06d07ca097e3306a4381635073ca91479966",
+                "sha256:14317396d1e8cdb122989b916fa2c7e9ca8e2be9e8060a6eff75b6b7b4d8a7e0"
             ],
             "markers": "python_version >= '3.6'",
-            "version": "==21.0"
+            "version": "==21.2"
         },
         "pathspec": {
             "hashes": [
-                "sha256:86379d6b86d75816baba717e64b1a3a3469deb93bb76d613c9ce79edc5cb68fd",
-                "sha256:aa0cb481c4041bf52ffa7b0d8fa6cd3e88a2ca4879c533c9153882ee2556790d"
+                "sha256:7d15c4ddb0b5c802d161efc417ec1a2558ea2653c2e8ad9c19098201dc1c993a",
+                "sha256:e564499435a2673d586f6b2130bb5b95f04a3ba06f81b8f895b651a3c76aabb1"
             ],
-            "version": "==0.8.1"
+            "version": "==0.9.0"
         },
         "pkginfo": {
             "hashes": [
-                "sha256:029a70cb45c6171c329dfc890cde0879f8c52d6f3922794796e06f577bb03db4",
-                "sha256:9fdbea6495622e022cc72c2e5e1b735218e4ffb2a2a69cde2694a6c1f16afb75"
+                "sha256:37ecd857b47e5f55949c41ed061eb51a0bee97a87c969219d144c0e023982779",
+                "sha256:e7432f81d08adec7297633191bbf0bd47faf13cd8724c3a13250e51d542635bd"
+            ],
+            "version": "==1.7.1"
+        },
+        "platformdirs": {
+            "hashes": [
+                "sha256:367a5e80b3d04d2428ffa76d33f124cf11e8fff2acdaa9b43d545f5c7d661ef2",
+                "sha256:8868bbe3c3c80d42f20156f22e7131d2fb321f5bc86a2a345375c6481a67021d"
             ],
-            "version": "==1.7.0"
+            "markers": "python_version >= '3.6'",
+            "version": "==2.4.0"
         },
         "pluggy": {
             "hashes": [
-                "sha256:15b2acde666561e1298d71b523007ed7364de07029219b604cf808bfa1c765b0",
-                "sha256:966c145cd83c96502c3c3868f50408687b38434af77734af1e9ca461a4081d2d"
+                "sha256:4224373bacce55f955a878bf9cfa763c1e360858e330072059e10bad68531159",
+                "sha256:74134bbf457f031a36d68416e1509f34bd5ccc019f0bcc952c7b909d06b37bd3"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==0.13.1"
+            "markers": "python_version >= '3.6'",
+            "version": "==1.0.0"
         },
         "pre-commit": {
             "hashes": [
-                "sha256:764972c60693dc668ba8e86eb29654ec3144501310f7198742a767bec385a378",
-                "sha256:b679d0fddd5b9d6d98783ae5f10fd0c4c59954f375b70a58cbe1ce9bcf9809a4"
+                "sha256:3c25add78dbdfb6a28a651780d5c311ac40dd17f160eb3954a0c59da40a505a7",
+                "sha256:a4ed01000afcb484d9eb8d504272e642c4c4099bbad3a6b27e519bd6a3e928a6"
             ],
             "index": "pypi",
-            "version": "==2.13.0"
+            "version": "==2.15.0"
         },
         "py": {
             "hashes": [
-                "sha256:21b81bda15b66ef5e1a777a21c4dcd9c20ad3efd0b3f817e7a809035269e1bd3",
-                "sha256:3b80836aa6d1feeaa108e046da6423ab8f6ceda6468545ae8d02d9d58d18818a"
+                "sha256:51c75c4126074b472f746a24399ad32f6053d1b34b68d2fa41e558e6f4a98719",
+                "sha256:607c53218732647dff4acdfcd50cb62615cedf612e72d1724fb1a0cc6405b378"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==1.10.0"
+            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
+            "version": "==1.11.0"
         },
         "pygments": {
             "hashes": [
-                "sha256:a18f47b506a429f6f4b9df81bb02beab9ca21d0a5fee38ed15aef65f0545519f",
-                "sha256:d66e804411278594d764fc69ec36ec13d9ae9147193a1740cd34d272ca383b8e"
+                "sha256:b8e67fe6af78f492b3c4b3e2970c0624cbf08beb1e493b2c99b9fa1b67a20380",
+                "sha256:f398865f7eb6874156579fdf36bc840a03cab64d1cde9e93d68f46a425ec52c6"
             ],
             "markers": "python_version >= '3.5'",
-            "version": "==2.9.0"
+            "version": "==2.10.0"
         },
         "pyparsing": {
             "hashes": [
@@ -224,107 +250,119 @@
         },
         "pytest": {
             "hashes": [
-                "sha256:50bcad0a0b9c5a72c8e4e7c9855a3ad496ca6a881a3641b4260605450772c54b",
-                "sha256:91ef2131a9bd6be8f76f1f08eac5c5317221d6ad1e143ae03894b862e8976890"
+                "sha256:131b36680866a76e6781d13f101efb86cf674ebb9762eb70d3082b6f29889e89",
+                "sha256:7310f8d27bc79ced999e760ca304d69f6ba6c6649c0b60fb0e04a4a77cacc134"
             ],
             "index": "pypi",
-            "version": "==6.2.4"
+            "version": "==6.2.5"
         },
         "pyyaml": {
             "hashes": [
-                "sha256:08682f6b72c722394747bddaf0aa62277e02557c0fd1c42cb853016a38f8dedf",
-                "sha256:0f5f5786c0e09baddcd8b4b45f20a7b5d61a7e7e99846e3c799b05c7c53fa696",
-                "sha256:129def1b7c1bf22faffd67b8f3724645203b79d8f4cc81f674654d9902cb4393",
-                "sha256:294db365efa064d00b8d1ef65d8ea2c3426ac366c0c4368d930bf1c5fb497f77",
-                "sha256:3b2b1824fe7112845700f815ff6a489360226a5609b96ec2190a45e62a9fc922",
-                "sha256:3bd0e463264cf257d1ffd2e40223b197271046d09dadf73a0fe82b9c1fc385a5",
-                "sha256:4465124ef1b18d9ace298060f4eccc64b0850899ac4ac53294547536533800c8",
-                "sha256:49d4cdd9065b9b6e206d0595fee27a96b5dd22618e7520c33204a4a3239d5b10",
-                "sha256:4e0583d24c881e14342eaf4ec5fbc97f934b999a6828693a99157fde912540cc",
-                "sha256:5accb17103e43963b80e6f837831f38d314a0495500067cb25afab2e8d7a4018",
-                "sha256:607774cbba28732bfa802b54baa7484215f530991055bb562efbed5b2f20a45e",
-                "sha256:6c78645d400265a062508ae399b60b8c167bf003db364ecb26dcab2bda048253",
-                "sha256:72a01f726a9c7851ca9bfad6fd09ca4e090a023c00945ea05ba1638c09dc3347",
-                "sha256:74c1485f7707cf707a7aef42ef6322b8f97921bd89be2ab6317fd782c2d53183",
-                "sha256:895f61ef02e8fed38159bb70f7e100e00f471eae2bc838cd0f4ebb21e28f8541",
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@@ -356,37 +394,79 @@
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+                "sha256:155b74b078be842d2eb630dd30a280025eca0a5383c7d45853c27afee65f278f",
+                "sha256:224afecb8b39739f5c9562794a7c98325cb9d972712e1a98b6989a4720219541",
+                "sha256:361b9e5d27bd8e3ccb6ea6ad6c4f3c0be322a1a0f8177db6d56264fa0ae40410",
+                "sha256:37ba2ab65a0028b1a4f2b61a8fe77f12d242731977d274a03d68ebb751271508",
+                "sha256:49af5b8f6f03ed1eb89ee06c1d7c2e7c8e743d720c3746a5857609a1abc94c94",
+                "sha256:51040bf45aacefa44fa67fb9ebcd1f2bec73182b99a532c2394eea7dabd18e24",
+                "sha256:52ca2b2b524d770bed7a393371a38e91943f9160a190141e0df911586066ecda",
+                "sha256:618912cbc7e17b4aeba86ffe071698c6e2d292acbd6d1d5ec1ee724b8c4ae450",
+                "sha256:65c81abbabda7d760df7304d843cc9dbe7ef5d485504ca59a46ae2d1731d2428",
+                "sha256:7b310a207ee9fde3f46ba327989e6cba4195bc0c8c70a158456e7b10233e6bed",
+                "sha256:7e6731044f748340ef68dcadb5172a4b1f40847a2983fe3983b2a66445fbc8e6",
+                "sha256:806e0c7346b9b4af8c62d9a29053f484599921a4448c37fbbcbbf15c25138570",
+                "sha256:a67fd5914603e2165e075f1b12f5a8356bfb9557e8bfb74511108cfbab0f51ed",
+                "sha256:e4374a76e61399a173137e7984a1d7e356038cf844f24fd8aea46c8029a2f712",
+                "sha256:e8a9b9c87801cecaad3b4c2b8876387115d1a14caa602c1618cedbb0cb2a14e6",
+                "sha256:ea517c2bb11c5e4ba7a83a91482a2837041181d57d3ed0749a6c382a2b6b7086",
+                "sha256:ec184dfb5d3d11e82841dbb973e7092b75f306b625fad7b2e665b64c5d60ab3f",
+                "sha256:ff4ad88271aa7a55f19b6a161ed44e088c393846d954729549e3cde8257747bb"
+            ],
+            "markers": "python_version < '3.8'",
+            "version": "==1.5.0"
+        },
+        "typing-extensions": {
+            "hashes": [
+                "sha256:49f75d16ff11f1cd258e1b988ccff82a3ca5570217d7ad8c5f48205dd99a677e",
+                "sha256:d8226d10bc02a29bcc81df19a26e56a9647f8b0a6d4a83924139f4a8b01f17b7",
+                "sha256:f1d25edafde516b146ecd0613dabcc61409817af4766fbbcfb8d1ad4ec441a34"
             ],
             "index": "pypi",
-            "version": "==3.4.1"
+            "version": "==3.10.0.2"
         },
         "urllib3": {
             "hashes": [
-                "sha256:39fb8672126159acb139a7718dd10806104dec1e2f0f6c88aab05d17df10c8d4",
-                "sha256:f57b4c16c62fa2760b7e3d97c35b255512fb6b59a259730f36ba32ce9f8e342f"
+                "sha256:4987c65554f7a2dbf30c18fd48778ef124af6fab771a377103da0585e2336ece",
+                "sha256:c4fdf4019605b6e5423637e01bc9fe4daef873709a7973e195ceba0a62bbc844"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4' and python_version < '4'",
-            "version": "==1.26.6"
+            "version": "==1.26.7"
         },
         "virtualenv": {
             "hashes": [
-                "sha256:14fdf849f80dbb29a4eb6caa9875d476ee2a5cf76a5f5415fa2f1606010ab467",
-                "sha256:2b0126166ea7c9c3661f5b8e06773d28f83322de7a3ff7d06f0aed18c9de6a76"
+                "sha256:4b02e52a624336eece99c96e3ab7111f469c24ba226a53ec474e8e787b365814",
+                "sha256:576d05b46eace16a9c348085f7d0dc8ef28713a2cabaa1cf0aea41e8f12c9218"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==20.4.7"
+            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3, 3.4'",
+            "version": "==20.10.0"
         },
         "webencodings": {
             "hashes": [
@@ -397,11 +477,11 @@
         },
         "zipp": {
             "hashes": [
-                "sha256:957cfda87797e389580cb8b9e3870841ca991e2125350677b2ca83a0e99390a3",
-                "sha256:f5812b1e007e48cff63449a5e9f4e7ebea716b4111f9c4f9a645f91d579bf0c4"
+                "sha256:71c644c5369f4a6e07636f0aa966270449561fcea2e3d6747b8d23efaa9d7832",
+                "sha256:9fe5ea21568a0a70e50f273397638d39b03353731e6cbbb3fd8502a33fec40bc"
             ],
             "markers": "python_version >= '3.6'",
-            "version": "==3.5.0"
+            "version": "==3.6.0"
         }
     }
 }
diff --git a/README.md b/README.md
index a2b1d62..cc7fe47 100644
--- a/README.md
+++ b/README.md
@@ -2,11 +2,11 @@
 
 This is an opinionated, simplified fork of [dbrgn/result](https://github.com/dbrgn/result).
 
-Result is a simple, type annotated Result type for Python 3.8+ inspired by [Rust](https://doc.rust-lang.org/std/result/).
+Result is a simple, type annotated Result type for Python 3.6+ inspired by [Rust](https://doc.rust-lang.org/std/result/).
 
 The idea is that a result value can be either `Ok(value)` or `Err(error)`, with a way to differentiate between the two. `Ok` and `Err` are both classes wrapping an arbitrary value. `Result[T, E]` is a generic type alias for `typing.Union[Ok[T], Err[E]]`.
 
-Requires Python 3.8 or higher!
+Requires Python 3.6 or higher!
 
 
 ### Caveats
diff --git a/setup.py b/setup.py
index c22e64a..a5906b1 100644
--- a/setup.py
+++ b/setup.py
@@ -17,11 +17,13 @@
         "License :: OSI Approved :: MIT License",
         "Programming Language :: Python :: 3",
         "Programming Language :: Python :: 3 :: Only",
+        "Programming Language :: Python :: 3.6",
+        "Programming Language :: Python :: 3.7",
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
     ],
     keywords="rust result",
     packages=["resultify"],
-    python_requires=">=3.8",
+    python_requires=">=3.6",
 )