diff --git a/Pipfile.lock b/Pipfile.lock
index 0c26f90d..6f07b19c 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -118,11 +118,11 @@
         },
         "bleach": {
             "hashes": [
-                "sha256:213336e49e102af26d9cde77dd2d0397afabc5a6bf2fed985dc35b5d1e285a16",
-                "sha256:3fdf7f77adcf649c9911387df51254b813185e32b2c6619f690b593a617e19fa"
+                "sha256:44f69771e2ac81ff30d929d485b7f9919f3ad6d019b6b20c74f3b8687c3f70df",
+                "sha256:aa8b870d0f46965bac2c073a93444636b0e1ca74e9777e34f03dd494b8a59d48"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==3.1.0"
+            "version": "==3.1.1"
         },
         "cached-property": {
             "hashes": [
@@ -146,41 +146,36 @@
         },
         "cffi": {
             "hashes": [
-                "sha256:0b49274afc941c626b605fb59b59c3485c17dc776dc3cc7cc14aca74cc19cc42",
-                "sha256:0e3ea92942cb1168e38c05c1d56b0527ce31f1a370f6117f1d490b8dcd6b3a04",
-                "sha256:135f69aecbf4517d5b3d6429207b2dff49c876be724ac0c8bf8e1ea99df3d7e5",
-                "sha256:19db0cdd6e516f13329cba4903368bff9bb5a9331d3410b1b448daaadc495e54",
-                "sha256:2781e9ad0e9d47173c0093321bb5435a9dfae0ed6a762aabafa13108f5f7b2ba",
-                "sha256:291f7c42e21d72144bb1c1b2e825ec60f46d0a7468f5346841860454c7aa8f57",
-                "sha256:2c5e309ec482556397cb21ede0350c5e82f0eb2621de04b2633588d118da4396",
-                "sha256:2e9c80a8c3344a92cb04661115898a9129c074f7ab82011ef4b612f645939f12",
-                "sha256:32a262e2b90ffcfdd97c7a5e24a6012a43c61f1f5a57789ad80af1d26c6acd97",
-                "sha256:3c9fff570f13480b201e9ab69453108f6d98244a7f495e91b6c654a47486ba43",
-                "sha256:415bdc7ca8c1c634a6d7163d43fb0ea885a07e9618a64bda407e04b04333b7db",
-                "sha256:42194f54c11abc8583417a7cf4eaff544ce0de8187abaf5d29029c91b1725ad3",
-                "sha256:4424e42199e86b21fc4db83bd76909a6fc2a2aefb352cb5414833c030f6ed71b",
-                "sha256:4a43c91840bda5f55249413037b7a9b79c90b1184ed504883b72c4df70778579",
-                "sha256:599a1e8ff057ac530c9ad1778293c665cb81a791421f46922d80a86473c13346",
-                "sha256:5c4fae4e9cdd18c82ba3a134be256e98dc0596af1e7285a3d2602c97dcfa5159",
-                "sha256:5ecfa867dea6fabe2a58f03ac9186ea64da1386af2159196da51c4904e11d652",
-                "sha256:62f2578358d3a92e4ab2d830cd1c2049c9c0d0e6d3c58322993cc341bdeac22e",
-                "sha256:6471a82d5abea994e38d2c2abc77164b4f7fbaaf80261cb98394d5793f11b12a",
-                "sha256:6d4f18483d040e18546108eb13b1dfa1000a089bcf8529e30346116ea6240506",
-                "sha256:71a608532ab3bd26223c8d841dde43f3516aa5d2bf37b50ac410bb5e99053e8f",
-                "sha256:74a1d8c85fb6ff0b30fbfa8ad0ac23cd601a138f7509dc617ebc65ef305bb98d",
-                "sha256:7b93a885bb13073afb0aa73ad82059a4c41f4b7d8eb8368980448b52d4c7dc2c",
-                "sha256:7d4751da932caaec419d514eaa4215eaf14b612cff66398dd51129ac22680b20",
-                "sha256:7f627141a26b551bdebbc4855c1157feeef18241b4b8366ed22a5c7d672ef858",
-                "sha256:8169cf44dd8f9071b2b9248c35fc35e8677451c52f795daa2bb4643f32a540bc",
-                "sha256:aa00d66c0fab27373ae44ae26a66a9e43ff2a678bf63a9c7c1a9a4d61172827a",
-                "sha256:ccb032fda0873254380aa2bfad2582aedc2959186cce61e3a17abc1a55ff89c3",
-                "sha256:d754f39e0d1603b5b24a7f8484b22d2904fa551fe865fd0d4c3332f078d20d4e",
-                "sha256:d75c461e20e29afc0aee7172a0950157c704ff0dd51613506bd7d82b718e7410",
-                "sha256:dcd65317dd15bc0451f3e01c80da2216a31916bdcffd6221ca1202d96584aa25",
-                "sha256:e570d3ab32e2c2861c4ebe6ffcad6a8abf9347432a37608fe1fbd157b3f0036b",
-                "sha256:fd43a88e045cf992ed09fa724b5315b790525f2676883a6ea64e3263bae6549d"
-            ],
-            "version": "==1.13.2"
+                "sha256:001bf3242a1bb04d985d63e138230802c6c8d4db3668fb545fb5005ddf5bb5ff",
+                "sha256:00789914be39dffba161cfc5be31b55775de5ba2235fe49aa28c148236c4e06b",
+                "sha256:028a579fc9aed3af38f4892bdcc7390508adabc30c6af4a6e4f611b0c680e6ac",
+                "sha256:14491a910663bf9f13ddf2bc8f60562d6bc5315c1f09c704937ef17293fb85b0",
+                "sha256:1cae98a7054b5c9391eb3249b86e0e99ab1e02bb0cc0575da191aedadbdf4384",
+                "sha256:2089ed025da3919d2e75a4d963d008330c96751127dd6f73c8dc0c65041b4c26",
+                "sha256:2d384f4a127a15ba701207f7639d94106693b6cd64173d6c8988e2c25f3ac2b6",
+                "sha256:337d448e5a725bba2d8293c48d9353fc68d0e9e4088d62a9571def317797522b",
+                "sha256:399aed636c7d3749bbed55bc907c3288cb43c65c4389964ad5ff849b6370603e",
+                "sha256:3b911c2dbd4f423b4c4fcca138cadde747abdb20d196c4a48708b8a2d32b16dd",
+                "sha256:3d311bcc4a41408cf5854f06ef2c5cab88f9fded37a3b95936c9879c1640d4c2",
+                "sha256:62ae9af2d069ea2698bf536dcfe1e4eed9090211dbaafeeedf5cb6c41b352f66",
+                "sha256:66e41db66b47d0d8672d8ed2708ba91b2f2524ece3dee48b5dfb36be8c2f21dc",
+                "sha256:675686925a9fb403edba0114db74e741d8181683dcf216be697d208857e04ca8",
+                "sha256:7e63cbcf2429a8dbfe48dcc2322d5f2220b77b2e17b7ba023d6166d84655da55",
+                "sha256:8a6c688fefb4e1cd56feb6c511984a6c4f7ec7d2a1ff31a10254f3c817054ae4",
+                "sha256:8c0ffc886aea5df6a1762d0019e9cb05f825d0eec1f520c51be9d198701daee5",
+                "sha256:95cd16d3dee553f882540c1ffe331d085c9e629499ceadfbda4d4fde635f4b7d",
+                "sha256:99f748a7e71ff382613b4e1acc0ac83bf7ad167fb3802e35e90d9763daba4d78",
+                "sha256:b8c78301cefcf5fd914aad35d3c04c2b21ce8629b5e4f4e45ae6812e461910fa",
+                "sha256:c420917b188a5582a56d8b93bdd8e0f6eca08c84ff623a4c16e809152cd35793",
+                "sha256:c43866529f2f06fe0edc6246eb4faa34f03fe88b64a0a9a942561c8e22f4b71f",
+                "sha256:cab50b8c2250b46fe738c77dbd25ce017d5e6fb35d3407606e7a4180656a5a6a",
+                "sha256:cef128cb4d5e0b3493f058f10ce32365972c554572ff821e175dbc6f8ff6924f",
+                "sha256:cf16e3cf6c0a5fdd9bc10c21687e19d29ad1fe863372b5543deaec1039581a30",
+                "sha256:e56c744aa6ff427a607763346e4170629caf7e48ead6921745986db3692f987f",
+                "sha256:e577934fc5f8779c554639376beeaa5657d54349096ef24abe8c74c5d9c117c3",
+                "sha256:f2b0fa0c01d8a0c7483afd9f31d7ecf2d71760ca24499c8697aeb5ca37dc090c"
+            ],
+            "version": "==1.14.0"
         },
         "cfgv": {
             "hashes": [
@@ -199,17 +194,11 @@
         },
         "click": {
             "hashes": [
-                "sha256:2335065e6395b9e67ca716de5f7526736bfa6ceead690adf616d925bdc622b13",
-                "sha256:5b94b49521f6456670fdb30cd82a4eca9412788a93fa6dd6df72c94d5a8ff2d7"
+                "sha256:8a18b4ea89d8820c5d0c7da8a64b2c324b4dabb695804dbfea19b9be9d88c0cc",
+                "sha256:e345d143d80bf5ee7534056164e5e112ea5e22716bbb1ce727941f4c8b471b9a"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==7.0"
-        },
-        "click-default-group": {
-            "hashes": [
-                "sha256:d9560e8e8dfa44b3562fbc9425042a0fd6d21956fcc2db0077f63f34253ab904"
-            ],
-            "version": "==1.2.2"
+            "version": "==7.1.1"
         },
         "cmarkgfm": {
             "hashes": [
@@ -331,10 +320,10 @@
         },
         "decorator": {
             "hashes": [
-                "sha256:54c38050039232e1db4ad7375cfce6748d7b41c29e95a081c8a6d2c30364a2ce",
-                "sha256:5d19b92a3c8f7f101c8dd86afd86b0f061a8ce4540ab8cd401fa2542756bce6d"
+                "sha256:41fa54c2a0cc4ba648be4fd43cff00aedf5b9465c9bf18d64325bc225f08f760",
+                "sha256:e3a62f0520172440ca0dcc823749319382e377f37f140a0b99ef45fecb84bfe7"
             ],
-            "version": "==4.4.1"
+            "version": "==4.4.2"
         },
         "distlib": {
             "hashes": [
@@ -342,13 +331,6 @@
             ],
             "version": "==0.3.0"
         },
-        "docopt": {
-            "hashes": [
-                "sha256:49b3a825280bd66b3aa83585ef59c4a8c82f2c8a522dbe754a8bc8d08c85c491",
-                "sha256:b2de412b0b73a5f16110cb1becdfbabceb3fd80811441183245938ff135ef9c1"
-            ],
-            "version": "==0.6.2"
-        },
         "docutils": {
             "hashes": [
                 "sha256:7a6228589435302e421f5c473ce0180878b90f70227f7174cacde5efbd34275f",
@@ -383,6 +365,13 @@
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
             "version": "==1.7.1"
         },
+        "filelock": {
+            "hashes": [
+                "sha256:18d82244ee114f543149c66a6e0c14e9c4f8a1044b5cdaadd0f82159d6a6ff59",
+                "sha256:929b7d63ec5b7d6b71b0fa5ac14e030b3f70b75747cef1b10da9b879fef15836"
+            ],
+            "version": "==3.0.12"
+        },
         "findimports": {
             "hashes": [
                 "sha256:6d6070bb373e9f5d135e53eea2253529ff7ef7b383aa5fe43856f6a173a65679",
@@ -407,11 +396,11 @@
         },
         "flake8-bugbear": {
             "hashes": [
-                "sha256:d8c466ea79d5020cb20bf9f11cf349026e09517a42264f313d3f6fddb83e0571",
-                "sha256:ded4d282778969b5ab5530ceba7aa1a9f1b86fa7618fc96a19a1d512331640f8"
+                "sha256:a3ddc03ec28ba2296fc6f89444d1c946a6b76460f859795b35b77d4920a51b63",
+                "sha256:bd02e4b009fb153fe6072c31c52aeab5b133d508095befb2ffcf3b41c4823162"
             ],
-            "markers": "python_version >= '3.5'",
-            "version": "==19.8.0"
+            "markers": "python_version > '3.5'",
+            "version": "==20.1.4"
         },
         "funcsigs": {
             "hashes": [
@@ -455,10 +444,11 @@
         },
         "idna": {
             "hashes": [
-                "sha256:c357b3f628cf53ae2c4c05627ecc484553142ca23264e593d327bcde5e9c3407",
-                "sha256:ea8b7f6188e6fa117537c3df7da9fc686d485087abf6ac197f9c46432f7e4a3c"
+                "sha256:7588d1c14ae4c77d74036e8c22ff447b26d0fde8f007354fd48a7814db15b7cb",
+                "sha256:a068a21ceac8a4d63dbfd964670474107f541babbd2250d61922f029858365fa"
             ],
-            "version": "==2.8"
+            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
+            "version": "==2.9"
         },
         "imagesize": {
             "hashes": [
@@ -500,11 +490,11 @@
         },
         "invoke": {
             "hashes": [
-                "sha256:c52274d2e8a6d64ef0d61093e1983268ea1fc0cd13facb9448c4ef0c9a7ac7da",
-                "sha256:f4ec8a134c0122ea042c8912529f87652445d9f4de590b353d23f95bfa1f0efd",
-                "sha256:fc803a5c9052f15e63310aa81a43498d7c55542beb18564db88a9d75a176fa44"
+                "sha256:87b3ef9d72a1667e104f89b159eaf8a514dbf2f3576885b2bbdefe74c3fb2132",
+                "sha256:93e12876d88130c8e0d7fd6618dd5387d6b36da55ad541481dfa5e001656f134",
+                "sha256:de3f23bfe669e3db1085789fd859eb8ca8e0c5d9c20811e2407fa042e8a5e15d"
             ],
-            "version": "==1.3.0"
+            "version": "==1.4.1"
         },
         "isort": {
             "hashes": [
@@ -524,58 +514,60 @@
         },
         "jeepney": {
             "hashes": [
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+                "sha256:d6c6b49683446d2407d2fe3acb7a368a77ff063f9182fe427da15d622adc24cf"
             ],
-            "markers": "python_version >= '3.5'",
-            "version": "==0.4.1"
+            "markers": "sys_platform == 'linux'",
+            "version": "==0.4.3"
         },
         "jinja2": {
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-                "sha256:9fe95f19286cfefaa917656583d020be14e7859c6b0252588391e47db34527de"
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-            "version": "==2.10.3"
+            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
+            "version": "==2.11.1"
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         "keyring": {
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-            "markers": "python_version >= '3.5'",
-            "version": "==19.3.0"
+            "markers": "python_version >= '3.6'",
+            "version": "==21.1.1"
         },
         "lxml": {
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+                "sha256:63dbc21efd7e822c11d5ddbedbbb08cd11a41e0032e382a0fd59b0b08e405a3a",
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+                "sha256:8620ce80f50d023d414183bf90cc2576c2837b88e00bea3f33ad2630133bbb60",
+                "sha256:8a0ebda56ebca1a83eb2d1ac266649b80af8dd4b4a3502b2c1e09ac2f88fe128",
+                "sha256:90ed0e36455a81b25b7034038e40880189169c308a3df360861ad74da7b68c1a",
+                "sha256:95e67224815ef86924fbc2b71a9dbd1f7262384bca4bc4793645794ac4200717",
+                "sha256:afdb34b715daf814d1abea0317b6d672476b498472f1e5aacbadc34ebbc26e89",
+                "sha256:b4b2c63cc7963aedd08a5f5a454c9f67251b1ac9e22fd9d72836206c42dc2a72",
+                "sha256:d068f55bda3c2c3fcaec24bd083d9e2eede32c583faf084d6e4b9daaea77dde8",
+                "sha256:d5b3c4b7edd2e770375a01139be11307f04341ec709cf724e0f26ebb1eef12c3",
+                "sha256:deadf4df349d1dcd7b2853a2c8796593cc346600726eff680ed8ed11812382a7",
+                "sha256:df533af6f88080419c5a604d0d63b2c33b1c0c4409aba7d0cb6de305147ea8c8",
+                "sha256:e4aa948eb15018a657702fee0b9db47e908491c64d36b4a90f59a64741516e77",
+                "sha256:e5d842c73e4ef6ed8c1bd77806bf84a7cb535f9c0cf9b2c74d02ebda310070e1",
+                "sha256:ebec08091a22c2be870890913bdadd86fcd8e9f0f22bcb398abd3af914690c15",
+                "sha256:edc15fcfd77395e24543be48871c251f38132bb834d9fdfdad756adb6ea37679",
+                "sha256:f2b74784ed7e0bc2d02bd53e48ad6ba523c9b36c194260b7a5045071abbb1012",
+                "sha256:fa071559f14bd1e92077b1b5f6c22cf09756c6de7139370249eb372854ce51e6",
+                "sha256:fd52e796fee7171c4361d441796b64df1acfceb51f29e545e812f16d023c4bbc",
+                "sha256:fe976a0f1ef09b3638778024ab9fb8cde3118f203364212c198f71341c0715ca"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==4.4.2"
+            "version": "==4.5.0"
         },
         "markupsafe": {
             "hashes": [
@@ -703,9 +695,9 @@
         },
         "nodeenv": {
             "hashes": [
-                "sha256:ad8259494cf1c9034539f6cced78a1da4840a4b157e23640bc4a0c0546b0cb7a"
+                "sha256:5b2438f2e42af54ca968dd1b374d14a1194848955187b0e5e4be1f73813a5212"
             ],
-            "version": "==1.3.3"
+            "version": "==1.3.5"
         },
         "orderedmultidict": {
             "hashes": [
@@ -716,26 +708,27 @@
         },
         "packaging": {
             "hashes": [
-                "sha256:28b924174df7a2fa32c1953825ff29c61e2f5e082343165438812f00d3a7fc47",
-                "sha256:d9551545c6d761f3def1677baf08ab2a3ca17c56879e70fecba2fc4dde4ed108"
+                "sha256:3c292b474fda1671ec57d46d739d072bfd495a4f51ad01a055121d81e952b7a3",
+                "sha256:82f77b9bee21c1bafbf35a84905d604d5d1223801d639cf3ed140bd651c08752"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==19.2"
+            "version": "==20.3"
         },
         "parso": {
             "hashes": [
-                "sha256:63854233e1fadb5da97f2744b6b24346d2750b85965e7e399bec1620232797dc",
-                "sha256:666b0ee4a7a1220f65d367617f2cd3ffddff3e205f3f16a0284df30e774c2a9c"
+                "sha256:0c5659e0c6eba20636f99a04f469798dca8da279645ce5c387315b2c23912157",
+                "sha256:8515fc12cfca6ee3aa59138741fc5624d62340c97e401c74875769948d4f2995"
             ],
-            "version": "==0.5.1"
+            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
+            "version": "==0.6.2"
         },
         "parver": {
             "hashes": [
-                "sha256:1b37a691af145a3a193eff269d53ba5b2ab16dfbb65d47d85360755919f5fe4b",
-                "sha256:72d056b8f8883ac90eef5554a9c8a47fac39d3b66479f3d2c8d5bc21b849cdba"
+                "sha256:b57d94e6f389f9db399bfc3ee4c4066f4cfb374ffef5727d5ae6a9c04eb8d228",
+                "sha256:bb9d19637c17819e276b5cf04e2dbfb81c4e2136da8873cc70dcd0e4fd3d14a3"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==0.2.1"
+            "version": "==0.3.0"
         },
         "pathlib2": {
             "hashes": [
@@ -766,11 +759,11 @@
         },
         "pip-shims": {
             "hashes": [
-                "sha256:383e054386d15f7a33d619a9fc19d670575cdf88e05a4dab93f0a254696ce836",
-                "sha256:d4b720d85a8cbd81f72ea22e273ac72415f1e0b49cade597b815c63b351d9637"
+                "sha256:5861da6f48e60b55d40b984795c63681e4db7ac576c1c3b05f4b54a9d508e3da",
+                "sha256:2b9a88ff0fd31e7d27a362d3e36e6e75d8fbc339c9c4367f4a97b72b22e6f4f4"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==0.4.0"
+            "version": "==0.5.1"
         },
         "pkginfo": {
             "hashes": [
@@ -800,11 +793,11 @@
         },
         "pre-commit": {
             "hashes": [
-                "sha256:9f152687127ec90642a2cc3e4d9e1e6240c4eb153615cb02aa1ad41d331cbb6e",
-                "sha256:c2e4810d2d3102d354947907514a78c5d30424d299dc0fe48f5aa049826e9b50"
+                "sha256:09ebe467f43ce24377f8c2f200fe3cd2570d328eb2ce0568c8e96ce19da45fa6",
+                "sha256:f8d555e31e2051892c7f7b3ad9f620bd2c09271d87e9eedb2ad831737d6211eb"
             ],
-            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==1.20.0"
+            "markers": "python_version >= '3.6'",
+            "version": "==2.1.1"
         },
         "prompt-toolkit": {
             "hashes": [
@@ -840,9 +833,11 @@
         },
         "pycparser": {
             "hashes": [
-                "sha256:a988718abfad80b6b157acce7bf130a30876d27603738ac39f140993246b25b3"
+                "sha256:2d475327684562c3a96cc71adf7dc8c4f0565175cf86b6d7a404ff4c771f15f0",
+                "sha256:7582ad22678f0fcd81102833f60ef8d0e57288b6b5fb00323d101be910e35705"
             ],
-            "version": "==2.19"
+            "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
+            "version": "==2.20"
         },
         "pyflakes": {
             "hashes": [
@@ -915,10 +910,10 @@
         },
         "pytype": {
             "hashes": [
-                "sha256:e6c7d3c01c70ea717709ad2a18bb7b2535504f88d06a965a04971d35c71d33b7"
+                "sha256:53803f0f1fadf4923efc88a0bd0cfa4c242d2fa3f04421b6f8ab4d658ffd2b90"
             ],
             "markers": "python_version >= '3.6'",
-            "version": "==2019.11.27"
+            "version": "==2020.2.6"
         },
         "pytz": {
             "hashes": [
@@ -955,29 +950,37 @@
         },
         "regex": {
             "hashes": [
-                "sha256:15454b37c5a278f46f7aa2d9339bda450c300617ca2fca6558d05d870245edc7",
-                "sha256:1ad40708c255943a227e778b022c6497c129ad614bb7a2a2f916e12e8a359ee7",
-                "sha256:5e00f65cc507d13ab4dfa92c1232d004fa202c1d43a32a13940ab8a5afe2fb96",
-                "sha256:604dc563a02a74d70ae1f55208ddc9bfb6d9f470f6d1a5054c4bd5ae58744ab1",
-                "sha256:720e34a539a76a1fedcebe4397290604cc2bdf6f81eca44adb9fb2ea071c0c69",
-                "sha256:7caf47e4a9ac6ef08cabd3442cc4ca3386db141fb3c8b2a7e202d0470028e910",
-                "sha256:7faf534c1841c09d8fefa60ccde7b9903c9b528853ecf41628689793290ca143",
-                "sha256:b4e0406d822aa4993ac45072a584d57aa4931cf8288b5455bbf30c1d59dbad59",
-                "sha256:c31eaf28c6fe75ea329add0022efeed249e37861c19681960f99bbc7db981fb2",
-                "sha256:c7393597191fc2043c744db021643549061e12abe0b3ff5c429d806de7b93b66",
-                "sha256:d2b302f8cdd82c8f48e9de749d1d17f85ce9a0f082880b9a4859f66b07037dc6",
-                "sha256:e3d8dd0ec0ea280cf89026b0898971f5750a7bd92cb62c51af5a52abd020054a",
-                "sha256:ec032cbfed59bd5a4b8eab943c310acfaaa81394e14f44454ad5c9eba4f24a74"
-            ],
-            "version": "==2019.11.1"
+                "sha256:01b2d70cbaed11f72e57c1cfbaca71b02e3b98f739ce33f5f26f71859ad90431",
+                "sha256:046e83a8b160aff37e7034139a336b660b01dbfe58706f9d73f5cdc6b3460242",
+                "sha256:113309e819634f499d0006f6200700c8209a2a8bf6bd1bdc863a4d9d6776a5d1",
+                "sha256:200539b5124bc4721247a823a47d116a7a23e62cc6695744e3eb5454a8888e6d",
+                "sha256:25f4ce26b68425b80a233ce7b6218743c71cf7297dbe02feab1d711a2bf90045",
+                "sha256:269f0c5ff23639316b29f31df199f401e4cb87529eafff0c76828071635d417b",
+                "sha256:5de40649d4f88a15c9489ed37f88f053c15400257eeb18425ac7ed0a4e119400",
+                "sha256:7f78f963e62a61e294adb6ff5db901b629ef78cb2a1cfce3cf4eeba80c1c67aa",
+                "sha256:82469a0c1330a4beb3d42568f82dffa32226ced006e0b063719468dcd40ffdf0",
+                "sha256:8c2b7fa4d72781577ac45ab658da44c7518e6d96e2a50d04ecb0fd8f28b21d69",
+                "sha256:974535648f31c2b712a6b2595969f8ab370834080e00ab24e5dbb9d19b8bfb74",
+                "sha256:99272d6b6a68c7ae4391908fc15f6b8c9a6c345a46b632d7fdb7ef6c883a2bbb",
+                "sha256:9b64a4cc825ec4df262050c17e18f60252cdd94742b4ba1286bcfe481f1c0f26",
+                "sha256:9e9624440d754733eddbcd4614378c18713d2d9d0dc647cf9c72f64e39671be5",
+                "sha256:9ff16d994309b26a1cdf666a6309c1ef51ad4f72f99d3392bcd7b7139577a1f2",
+                "sha256:b33ebcd0222c1d77e61dbcd04a9fd139359bded86803063d3d2d197b796c63ce",
+                "sha256:bba52d72e16a554d1894a0cc74041da50eea99a8483e591a9edf1025a66843ab",
+                "sha256:bed7986547ce54d230fd8721aba6fd19459cdc6d315497b98686d0416efaff4e",
+                "sha256:c7f58a0e0e13fb44623b65b01052dae8e820ed9b8b654bb6296bc9c41f571b70",
+                "sha256:d58a4fa7910102500722defbde6e2816b0372a4fcc85c7e239323767c74f5cbc",
+                "sha256:f1ac2dc65105a53c1c2d72b1d3e98c2464a133b4067a51a3d2477b28449709a0"
+            ],
+            "version": "==2020.2.20"
         },
         "requests": {
             "hashes": [
-                "sha256:11e007a8a2aa0323f5a921e9e6a2d7e4e67d9877e85773fba9ba6419025cbeb4",
-                "sha256:9cf5292fcd0f598c671cfc1e0d7d1a7f13bb8085e9a590f48c010551dc6c4b31"
+                "sha256:43999036bfa82904b6af1d99e4882b560e5e2c68e5c4b0aa03b655f3d7d73fee",
+                "sha256:b3f43d496c6daba4493e7c431722aeb7dbc6288f52a6e04e7b6023b0247817e6"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==2.22.0"
+            "version": "==2.23.0"
         },
         "requests-toolbelt": {
             "hashes": [
@@ -1139,11 +1142,11 @@
         },
         "tomlkit": {
             "hashes": [
-                "sha256:32c10cc16ded7e4101c79f269910658cc2a0be5913f1252121c3cd603051c269",
-                "sha256:96e6369288571799a3052c1ef93b9de440e1ab751aa045f435b55e9d3bcd0690"
+                "sha256:4e1bd6c9197d984528f9ff0cc9db667c317d8881288db50db20eeeb0f6b0380b",
+                "sha256:f044eda25647882e5ef22b43a1688fb6ab12af2fc50e8456cdfc751c873101cf"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==0.5.8"
+            "version": "==0.5.11"
         },
         "towncrier": {
             "hashes": [
@@ -1154,11 +1157,11 @@
         },
         "tqdm": {
             "hashes": [
-                "sha256:156a0565f09d1f0ef8242932a0e1302462c93827a87ba7b4423d90f01befe94c",
-                "sha256:c0ffb55959ea5f3eaeece8d2db0651ba9ced9c72f40a6cce3419330256234289"
+                "sha256:0d8b5afb66e23d80433102e9bd8b5c8b65d34c2a2255b2de58d97bd2ea8170fd",
+                "sha256:f35fb121bafa030bd94e74fcfd44f3c2830039a2ddef7fc87ef1c2d205237b24"
             ],
             "markers": "python_version >= '2.6' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==4.40.0"
+            "version": "==4.43.0"
         },
         "twine": {
             "hashes": [
@@ -1222,11 +1225,11 @@
         },
         "virtualenv": {
             "hashes": [
-                "sha256:116655188441670978117d0ebb6451eb6a7526f9ae0796cc0dee6bd7356909b0",
-                "sha256:b57776b44f91511866594e477dd10e76a6eb44439cdd7f06dcd30ba4c5bd854f"
+                "sha256:10750cac3b5a9e6eed54d0f1f8222c550dc47f84609c95cbc504d44a58a048b8",
+                "sha256:8512e83f1d90f8e481024d58512ac9c053bf16f54d9138520a0929396820dd78"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==16.7.8"
+            "version": "==20.0.10"
         },
         "vistir": {
             "hashes": [
@@ -1238,17 +1241,17 @@
         },
         "vulture": {
             "hashes": [
-                "sha256:c200a01ec47c05d75c5feffe096aeb85a4d3f0e18563be125fae72c13b584ea5",
-                "sha256:d303d4778b44aebd4de76080138b9dd9b1c9c50b94bb9aaa5508f1abd7d94220"
+                "sha256:4da42bee8968906fb1f47c64008817515baec8ccff0c31746d1573103a6e920c",
+                "sha256:54f013779e071c7e1657e3a0b567f7400e046a8beb08585179ffbe762661fb5e"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==1.2"
+            "version": "==1.3"
         },
         "watchdog": {
             "hashes": [
-                "sha256:965f658d0732de3188211932aeb0bb457587f04f63ab4c1e33eab878e9de961d"
+                "sha256:c560efb643faed5ef28784b2245cf8874f939569717a4a12826a173ac644456b"
             ],
-            "version": "==0.9.0"
+            "version": "==0.10.2"
         },
         "wcwidth": {
             "hashes": [
@@ -1266,11 +1269,11 @@
         },
         "wheel": {
             "hashes": [
-                "sha256:10c9da68765315ed98850f8e048347c3eb06dd81822dc2ab1d4fde9dc9702646",
-                "sha256:f4da1763d3becf2e2cd92a14a7c920f0f00eca30fdde9ea992c836685b9faf28"
+                "sha256:8788e9155fe14f54164c1b9eb0a319d98ef02c160725587ad60f14ddc57b6f96",
+                "sha256:df277cb51e61359aba502208d680f90c0493adec6f0e848af94948778aed386e"
             ],
             "markers": "python_version >= '2.7' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==0.33.6"
+            "version": "==0.34.2"
         },
         "zipp": {
             "hashes": [
diff --git a/src/requirementslib/models/dependencies.py b/src/requirementslib/models/dependencies.py
index 2b42df89..5e69b137 100644
--- a/src/requirementslib/models/dependencies.py
+++ b/src/requirementslib/models/dependencies.py
@@ -32,6 +32,11 @@
     version_from_ireq,
 )
 
+try:
+    from contextlib import ExitStack
+except ImportError:
+    from contextlib2 import ExitStack
+
 if MYPY_RUNNING:
     from typing import (
         Any,
@@ -646,18 +651,22 @@ def start_resolver(finder=None, session=None, wheel_cache=None):
     _build_dir = create_tracked_tempdir(fs_str("build"))
     _source_dir = create_tracked_tempdir(fs_str("source"))
     try:
-        with pip_shims.shims.make_preparer(
-            options=pip_options,
-            finder=finder,
-            session=session,
-            build_dir=_build_dir,
-            src_dir=_source_dir,
-            download_dir=download_dir,
-            wheel_download_dir=WHEEL_DOWNLOAD_DIR,
-            progress_bar="off",
-            build_isolation=False,
-            install_cmd=pip_command,
-        ) as preparer:
+        with ExitStack() as ctx:
+            ctx.enter_context(pip_shims.shims.global_tempdir_manager())
+            preparer = ctx.enter_context(
+                pip_shims.shims.make_preparer(
+                    options=pip_options,
+                    finder=finder,
+                    session=session,
+                    build_dir=_build_dir,
+                    src_dir=_source_dir,
+                    download_dir=download_dir,
+                    wheel_download_dir=WHEEL_DOWNLOAD_DIR,
+                    progress_bar="off",
+                    build_isolation=False,
+                    install_cmd=pip_command,
+                )
+            )
             resolver = pip_shims.shims.get_resolver(
                 finder=finder,
                 ignore_dependencies=False,
diff --git a/src/requirementslib/models/setup_info.py b/src/requirementslib/models/setup_info.py
index 8ad73731..47846e5b 100644
--- a/src/requirementslib/models/setup_info.py
+++ b/src/requirementslib/models/setup_info.py
@@ -1489,17 +1489,17 @@ def from_ireq(cls, ireq, subdir=None, finder=None, session=None):
         build_location_func(kwargs["build_dir"])
         ireq.ensure_has_source_dir(kwargs["src_dir"])
         src_dir = ireq.source_dir
-
-        ireq.populate_link(finder, False, False)
-        pip_shims.shims.shim_unpack(
-            link=ireq.link,
-            location=kwargs["src_dir"],
-            download_dir=download_dir,
-            only_download=only_download,
-            session=session,
-            hashes=ireq.hashes(False),
-            progress_bar="off",
-        )
+        with pip_shims.shims.global_tempdir_manager():
+            ireq.populate_link(finder, False, False)
+            pip_shims.shims.shim_unpack(
+                link=ireq.link,
+                location=kwargs["src_dir"],
+                download_dir=download_dir,
+                only_download=only_download,
+                session=session,
+                hashes=ireq.hashes(False),
+                progress_bar="off",
+            )
         created = cls.create(src_dir, subdirectory=subdir, ireq=ireq, kwargs=kwargs)
         return created
 
diff --git a/src/requirementslib/models/vcs.py b/src/requirementslib/models/vcs.py
index 447e54e4..2cd62249 100644
--- a/src/requirementslib/models/vcs.py
+++ b/src/requirementslib/models/vcs.py
@@ -61,15 +61,17 @@ def is_local(self):
 
     def obtain(self):
         # type: () -> None
-        lte_pip_19 = (
-            pip_shims.parsed_pip_version.parsed_version < pip_shims.parse_version("19.0")
+        lt_pip_19_2 = (
+            pip_shims.parsed_pip_version.parsed_version < pip_shims.parse_version("19.2")
         )
+        if lt_pip_19_2:
+            self.repo_backend = self.repo_backend(self.url)
         if os.path.exists(
             self.checkout_directory
         ) and not self.repo_backend.is_repository_directory(self.checkout_directory):
             self.repo_backend.unpack(self.checkout_directory)
         elif not os.path.exists(self.checkout_directory):
-            if lte_pip_19:
+            if lt_pip_19_2:
                 self.repo_backend.obtain(self.checkout_directory)
             else:
                 self.repo_backend.obtain(self.checkout_directory, self.parsed_url)