diff --git a/Pipfile b/Pipfile
index d8778ec..cd04bf7 100644
--- a/Pipfile
+++ b/Pipfile
@@ -15,4 +15,4 @@ ipython = "*"
 pytest = "*"
 
 [requires]
-python_version = "3.7"
+python_version = "3.8"
diff --git a/Pipfile.lock b/Pipfile.lock
index cfec8b7..f3ee843 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -1,11 +1,11 @@
 {
     "_meta": {
         "hash": {
-            "sha256": "b0152688b12e9a7d176f42fd1940613deedc79e6a561edc1d86ed9248cbe4255"
+            "sha256": "97e81a39aace7e0a0436f569e583c9c430aaccd6fc3a5e0169c78c9fa57e5e5e"
         },
         "pipfile-spec": 6,
         "requires": {
-            "python_version": "3.7"
+            "python_version": "3.8"
         },
         "sources": [
             {
@@ -18,10 +18,10 @@
     "default": {
         "certifi": {
             "hashes": [
-                "sha256:046832c04d4e752f37383b628bc601a7ea7211496b4638f6514d0e5b9acc4939",
-                "sha256:945e3ba63a0b9f577b1395204e13c3a231f9bc0223888be653286534e5873695"
+                "sha256:e4f3620cfea4f83eedc95b24abd9cd56f3c4b146dd0177e83a21b4eb49e21e50",
+                "sha256:fd7c7c74727ddcf00e9acd26bba8da604ffec95bf1c2144e67aff7a8b50e6cef"
             ],
-            "version": "==2019.6.16"
+            "version": "==2019.9.11"
         },
         "chardet": {
             "hashes": [
@@ -52,11 +52,11 @@
         },
         "gunicorn": {
             "hashes": [
-                "sha256:aa8e0b40b4157b36a5df5e599f45c9c76d6af43845ba3b3b0efe2c70473c2471",
-                "sha256:fa2662097c66f920f53f70621c6c58ca4a3c4d3434205e608e121b5b3b71f4f3"
+                "sha256:0806b5e8a2eb8ba9ac1be65d7b743ec896fc25f5d6cb16c5e051540157b315bb",
+                "sha256:ef69dea4814df95e64e3f40b47b7ffedc6911c5009233be9d01cfd0d14aa3f50"
             ],
             "index": "pypi",
-            "version": "==19.9.0"
+            "version": "==20.0.0"
         },
         "idna": {
             "hashes": [
@@ -67,37 +67,41 @@
         },
         "psycopg2-binary": {
             "hashes": [
-                "sha256:080c72714784989474f97be9ab0ddf7b2ad2984527e77f2909fcd04d4df53809",
-                "sha256:110457be80b63ff4915febb06faa7be002b93a76e5ba19bf3f27636a2ef58598",
-                "sha256:171352a03b22fc099f15103959b52ee77d9a27e028895d7e5fde127aa8e3bac5",
-                "sha256:19d013e7b0817087517a4b3cab39c084d78898369e5c46258aab7be4f233d6a1",
-                "sha256:249b6b21ae4eb0f7b8423b330aa80fab5f821b9ffc3f7561a5e2fd6bb142cf5d",
-                "sha256:2ac0731d2d84b05c7bb39e85b7e123c3a0acd4cda631d8d542802c88deb9e87e",
-                "sha256:2b6d561193f0dc3f50acfb22dd52ea8c8dfbc64bcafe3938b5f209cc17cb6f00",
-                "sha256:2bd23e242e954214944481124755cbefe7c2cf563b1a54cd8d196d502f2578bf",
-                "sha256:3e1239242ca60b3725e65ab2f13765fc199b03af9eaf1b5572f0e97bdcee5b43",
-                "sha256:3eb70bb697abbe86b1d2b1316370c02ba320bfd1e9e35cf3b9566a855ea8e4e5",
-                "sha256:51a2fc7e94b98bd1bb5d4570936f24fc2b0541b63eccadf8fdea266db8ad2f70",
-                "sha256:52f1bdafdc764b7447e393ed39bb263eccb12bfda25a4ac06d82e3a9056251f6",
-                "sha256:5b3581319a3951f1e866f4f6c5e42023db0fae0284273b82e97dfd32c51985cd",
-                "sha256:63c1b66e3b2a3a336288e4bcec499e0dc310cd1dceaed1c46fa7419764c68877",
-                "sha256:8123a99f24ecee469e5c1339427bcdb2a33920a18bb5c0d58b7c13f3b0298ba3",
-                "sha256:85e699fcabe7f817c0f0a412d4e7c6627e00c412b418da7666ff353f38e30f67",
-                "sha256:8dbff4557bbef963697583366400822387cccf794ccb001f1f2307ed21854c68",
-                "sha256:908d21d08d6b81f1b7e056bbf40b2f77f8c499ab29e64ec5113052819ef1c89b",
-                "sha256:af39d0237b17d0a5a5f638e9dffb34013ce2b1d41441fd30283e42b22d16858a",
-                "sha256:af51bb9f055a3f4af0187149a8f60c9d516cf7d5565b3dac53358796a8fb2a5b",
-                "sha256:b2ecac57eb49e461e86c092761e6b8e1fd9654dbaaddf71a076dcc869f7014e2",
-                "sha256:cd37cc170678a4609becb26b53a2bc1edea65177be70c48dd7b39a1149cabd6e",
-                "sha256:d17e3054b17e1a6cb8c1140f76310f6ede811e75b7a9d461922d2c72973f583e",
-                "sha256:d305313c5a9695f40c46294d4315ed3a07c7d2b55e48a9010dad7db7a66c8b7f",
-                "sha256:dd0ef0eb1f7dd18a3f4187226e226a7284bda6af5671937a221766e6ef1ee88f",
-                "sha256:e1adff53b56db9905db48a972fb89370ad5736e0450b96f91bcf99cadd96cfd7",
-                "sha256:f0d43828003c82dbc9269de87aa449e9896077a71954fbbb10a614c017e65737",
-                "sha256:f78e8b487de4d92640105c1389e5b90be3496b1d75c90a666edd8737cc2dbab7"
+                "sha256:040234f8a4a8dfd692662a8308d78f63f31a97e1c42d2480e5e6810c48966a29",
+                "sha256:086f7e89ec85a6704db51f68f0dcae432eff9300809723a6e8782c41c2f48e03",
+                "sha256:18ca813fdb17bc1db73fe61b196b05dd1ca2165b884dd5ec5568877cabf9b039",
+                "sha256:19dc39616850342a2a6db70559af55b22955f86667b5f652f40c0e99253d9881",
+                "sha256:2166e770cb98f02ed5ee2b0b569d40db26788e0bf2ec3ae1a0d864ea6f1d8309",
+                "sha256:3a2522b1d9178575acee4adf8fd9f979f9c0449b00b4164bb63c3475ea6528ed",
+                "sha256:3aa773580f85a28ffdf6f862e59cb5a3cc7ef6885121f2de3fca8d6ada4dbf3b",
+                "sha256:3b5deaa3ee7180585a296af33e14c9b18c218d148e735c7accf78130765a47e3",
+                "sha256:407af6d7e46593415f216c7f56ba087a9a42bd6dc2ecb86028760aa45b802bd7",
+                "sha256:4c3c09fb674401f630626310bcaf6cd6285daf0d5e4c26d6e55ca26a2734e39b",
+                "sha256:4c6717962247445b4f9e21c962ea61d2e884fc17df5ddf5e35863b016f8a1f03",
+                "sha256:50446fae5681fc99f87e505d4e77c9407e683ab60c555ec302f9ac9bffa61103",
+                "sha256:5057669b6a66aa9ca118a2a860159f0ee3acf837eda937bdd2a64f3431361a2d",
+                "sha256:5dd90c5438b4f935c9d01fcbad3620253da89d19c1f5fca9158646407ed7df35",
+                "sha256:659c815b5b8e2a55193ede2795c1e2349b8011497310bb936da7d4745652823b",
+                "sha256:69b13fdf12878b10dc6003acc8d0abf3ad93e79813fd5f3812497c1c9fb9be49",
+                "sha256:7a1cb80e35e1ccea3e11a48afe65d38744a0e0bde88795cc56a4d05b6e4f9d70",
+                "sha256:7e6e3c52e6732c219c07bd97fff6c088f8df4dae3b79752ee3a817e6f32e177e",
+                "sha256:7f42a8490c4fe854325504ce7a6e4796b207960dabb2cbafe3c3959cb00d1d7e",
+                "sha256:84156313f258eafff716b2961644a4483a9be44a5d43551d554844d15d4d224e",
+                "sha256:8578d6b8192e4c805e85f187bc530d0f52ba86c39172e61cd51f68fddd648103",
+                "sha256:890167d5091279a27e2505ff0e1fb273f8c48c41d35c5b92adbf4af80e6b2ed6",
+                "sha256:98e10634792ac0e9e7a92a76b4991b44c2325d3e7798270a808407355e7bb0a1",
+                "sha256:9aadff9032e967865f9778485571e93908d27dab21d0fdfdec0ca779bb6f8ad9",
+                "sha256:9f24f383a298a0c0f9b3113b982e21751a8ecde6615494a3f1470eb4a9d70e9e",
+                "sha256:a73021b44813b5c84eda4a3af5826dd72356a900bac9bd9dd1f0f81ee1c22c2f",
+                "sha256:afd96845e12638d2c44d213d4810a08f4dc4a563f9a98204b7428e567014b1cd",
+                "sha256:b73ddf033d8cd4cc9dfed6324b1ad2a89ba52c410ef6877998422fcb9c23e3a8",
+                "sha256:b8f490f5fad1767a1331df1259763b3bad7d7af12a75b950c2843ba319b2415f",
+                "sha256:dbc5cd56fff1a6152ca59445178652756f4e509f672e49ccdf3d79c1043113a4",
+                "sha256:eac8a3499754790187bb00574ab980df13e754777d346f85e0ff6df929bcd964",
+                "sha256:eaed1c65f461a959284649e37b5051224f4db6ebdc84e40b5e65f2986f101a08"
             ],
             "index": "pypi",
-            "version": "==2.8.3"
+            "version": "==2.8.4"
         },
         "requests": {
             "hashes": [
@@ -109,10 +113,10 @@
         },
         "urllib3": {
             "hashes": [
-                "sha256:b246607a25ac80bedac05c6f282e3cdaf3afb65420fd024ac94435cabe6e18d1",
-                "sha256:dbe59173209418ae49d485b87d1681aefa36252ee85884c31346debd19463232"
+                "sha256:a8a318824cc77d1fd4b2bec2ded92646630d7fe8619497b142c84a9e6f5a7293",
+                "sha256:f3c5fd51747d450d4dcf6f923c81f78f811aab8205fda64b0aba34a4e48b0745"
             ],
-            "version": "==1.25.3"
+            "version": "==1.25.7"
         }
     },
     "develop": {
@@ -125,10 +129,10 @@
         },
         "attrs": {
             "hashes": [
-                "sha256:69c0dbf2ed392de1cb5ec704444b08a5ef81680a61cb899dc08127123af36a79",
-                "sha256:f0b870f674851ecbfbbbd364d6b5cbdff9dcedbc7f3f5e18a6891057f21fe399"
+                "sha256:08a96c641c3a74e44eb59afb61a24f2cb9f4d7188748e76ba4bb5edfa3cb7d1c",
+                "sha256:f7b7ce16570fe9965acd6d30101a28f62fb4a7f9e926b3bbc9b61f8b04247e72"
             ],
-            "version": "==19.1.0"
+            "version": "==19.3.0"
         },
         "backcall": {
             "hashes": [
@@ -139,10 +143,10 @@
         },
         "decorator": {
             "hashes": [
-                "sha256:86156361c50488b84a3f148056ea716ca587df2f0de1d34750d35c21312725de",
-                "sha256:f069f3a01830ca754ba5258fde2278454a0b5b79e0d7f5c13b3b97e57d4acff6"
+                "sha256:54c38050039232e1db4ad7375cfce6748d7b41c29e95a081c8a6d2c30364a2ce",
+                "sha256:5d19b92a3c8f7f101c8dd86afd86b0f061a8ce4540ab8cd401fa2542756bce6d"
             ],
-            "version": "==4.4.0"
+            "version": "==4.4.1"
         },
         "entrypoints": {
             "hashes": [
@@ -153,27 +157,19 @@
         },
         "flake8": {
             "hashes": [
-                "sha256:19241c1cbc971b9962473e4438a2ca19749a7dd002dd1a946eaba171b4114548",
-                "sha256:8e9dfa3cecb2400b3738a42c54c3043e821682b9c840b0448c0503f781130696"
+                "sha256:45681a117ecc81e870cbf1262835ae4af5e7a8b08e40b944a8a6e6b895914cfb",
+                "sha256:49356e766643ad15072a789a20915d3c91dc89fd313ccd71802303fd67e4deca"
             ],
             "index": "pypi",
-            "version": "==3.7.8"
-        },
-        "importlib-metadata": {
-            "hashes": [
-                "sha256:23d3d873e008a513952355379d93cbcab874c58f4f034ff657c7a87422fa64e8",
-                "sha256:80d2de76188eabfbfcf27e6a37342c2827801e59c4cc14b0371c56fed43820e3"
-            ],
-            "markers": "python_version < '3.8'",
-            "version": "==0.19"
+            "version": "==3.7.9"
         },
         "ipython": {
             "hashes": [
-                "sha256:1d3a1692921e932751bc1a1f7bb96dc38671eeefdc66ed33ee4cbc57e92a410e",
-                "sha256:537cd0176ff6abd06ef3e23f2d0c4c2c8a4d9277b7451544c6cbf56d1c79a83d"
+                "sha256:dfd303b270b7b5232b3d08bd30ec6fd685d8a58cabd54055e3d69d8f029f7280",
+                "sha256:ed7ebe1cba899c1c3ccad6f7f1c2d2369464cc77dba8eebc65e2043e19cda995"
             ],
             "index": "pypi",
-            "version": "==7.7.0"
+            "version": "==7.9.0"
         },
         "ipython-genutils": {
             "hashes": [
@@ -205,10 +201,10 @@
         },
         "packaging": {
             "hashes": [
-                "sha256:a7ac867b97fdc07ee80a8058fe4435ccd274ecc3b0ed61d852d7d53055528cf9",
-                "sha256:c491ca87294da7cc01902edbe30a5bc6c4c28172b5138ab4e4aa1b9d7bfaeafe"
+                "sha256:28b924174df7a2fa32c1953825ff29c61e2f5e082343165438812f00d3a7fc47",
+                "sha256:d9551545c6d761f3def1677baf08ab2a3ca17c56879e70fecba2fc4dde4ed108"
             ],
-            "version": "==19.1"
+            "version": "==19.2"
         },
         "parso": {
             "hashes": [
@@ -234,18 +230,18 @@
         },
         "pluggy": {
             "hashes": [
-                "sha256:0825a152ac059776623854c1543d65a4ad408eb3d33ee114dff91e57ec6ae6fc",
-                "sha256:b9817417e95936bf75d85d3f8767f7df6cdde751fc40aed3bb3074cbcb77757c"
+                "sha256:0db4b7601aae1d35b4a033282da476845aa19185c1e6964b25cf324b5e4ec3e6",
+                "sha256:fa5fa1622fa6dd5c030e9cad086fa19ef6a0cf6d7a2d12318e10cb49d6d68f34"
             ],
-            "version": "==0.12.0"
+            "version": "==0.13.0"
         },
         "prompt-toolkit": {
             "hashes": [
-                "sha256:11adf3389a996a6d45cc277580d0d53e8a5afd281d0c9ec71b28e6f121463780",
-                "sha256:2519ad1d8038fd5fc8e770362237ad0364d16a7650fb5724af6997ed5515e3c1",
-                "sha256:977c6583ae813a37dc1c2e1b715892461fcbdaa57f6fc62f33a528c4886c8f55"
+                "sha256:46642344ce457641f28fc9d1c9ca939b63dadf8df128b86f1b9860e59c73a5e4",
+                "sha256:e7f8af9e3d70f514373bf41aa51bc33af12a6db3f71461ea47fea985defb2c31",
+                "sha256:f15af68f66e664eaa559d4ac8a928111eebd5feda0c11738b5998045224829db"
             ],
-            "version": "==2.0.9"
+            "version": "==2.0.10"
         },
         "ptyprocess": {
             "hashes": [
@@ -284,32 +280,32 @@
         },
         "pyparsing": {
             "hashes": [
-                "sha256:6f98a7b9397e206d78cc01df10131398f1c8b8510a2f4d97d9abd82e1aacdd80",
-                "sha256:d9338df12903bbf5d65a0e4e87c2161968b10d2e489652bb47001d82a9b028b4"
+                "sha256:20f995ecd72f2a1f4bf6b072b63b22e2eb457836601e76d6e5dfcd75436acc1f",
+                "sha256:4ca62001be367f01bd3e92ecbb79070272a9d4964dce6a48a82ff0b8bc7e683a"
             ],
-            "version": "==2.4.2"
+            "version": "==2.4.5"
         },
         "pytest": {
             "hashes": [
-                "sha256:95b1f6db806e5b1b5b443efeb58984c24945508f93a866c1719e1a507a957d7c",
-                "sha256:c3d5020755f70c82eceda3feaf556af9a341334414a8eca521a18f463bcead88"
+                "sha256:15837d2880cb94821087bc07476892ea740696b20e90288fd6c19e44b435abdb",
+                "sha256:b6cf7ad9064049ee486586b3a0ddd70dc5136c40e1147e7d286efd77ba66c5eb"
             ],
             "index": "pypi",
-            "version": "==5.1.1"
+            "version": "==5.2.3"
         },
         "six": {
             "hashes": [
-                "sha256:3350809f0555b11f552448330d0b52d5f24c91a322ea4a15ef22629740f3761c",
-                "sha256:d16a0141ec1a18405cd4ce8b4613101da75da0e9a7aec5bdd4fa804d0e0eba73"
+                "sha256:1f1b7d42e254082a9db6279deae68afb421ceba6158efa6131de7b3003ee93fd",
+                "sha256:30f610279e8b2578cab6db20741130331735c781b56053c59c4076da27f06b66"
             ],
-            "version": "==1.12.0"
+            "version": "==1.13.0"
         },
         "traitlets": {
             "hashes": [
-                "sha256:9c4bd2d267b7153df9152698efb1050a5d84982d3384a37b2c1f7723ba3e7835",
-                "sha256:c6cb5e6f57c5a9bdaa40fa71ce7b4af30298fbab9ece9815b5d995ab6217c7d9"
+                "sha256:70b4c6a1d9019d7b4f6846832288f86998aa3b9207c6821f3578a6a6a467fe44",
+                "sha256:d023ee369ddd2763310e4c3eae1ff649689440d4ae59d7485eb4cfbbe3e359f7"
             ],
-            "version": "==4.3.2"
+            "version": "==4.3.3"
         },
         "wcwidth": {
             "hashes": [
@@ -317,13 +313,6 @@
                 "sha256:f4ebe71925af7b40a864553f761ed559b43544f8f71746c2d756c7fe788ade7c"
             ],
             "version": "==0.1.7"
-        },
-        "zipp": {
-            "hashes": [
-                "sha256:3718b1cbcd963c7d4c5511a8240812904164b7f381b647143a89d3b98f9bcd8e",
-                "sha256:f06903e9f1f43b12d371004b4ac7b06ab39a44adc747266928ae6debfa7b3335"
-            ],
-            "version": "==0.6.0"
         }
     }
 }