diff --git a/poetry.lock b/poetry.lock
index de4ce21..430da0f 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -598,7 +598,7 @@ description = "Optional static typing for Python"
 name = "mypy"
 optional = false
 python-versions = ">=3.5"
-version = "0.730"
+version = "0.740"
 
 [package.dependencies]
 mypy-extensions = ">=0.4.0,<0.5.0"
@@ -1146,7 +1146,7 @@ version = "0.6.0"
 more-itertools = "*"
 
 [metadata]
-content-hash = "fe69450d2b6e62dbfdccf7fe366fce6b5138aff8f2325a9314c5a3f6458847e8"
+content-hash = "f68c0027e06c7a614859975d8c94a4754e59f23ebb52947743245b171d65589d"
 python-versions = "^3.6"
 
 [metadata.hashes]
@@ -1208,7 +1208,7 @@ marshmallow-polyfield = ["963a01e80bca5cb4da42b8d2f7e6e90946257ae22d22ff2ed104a8
 mccabe = ["ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42", "dd8d182285a0fe56bace7f45b5e7d1a6ebcbf524e8f3bd87eb0f125271b8831f"]
 mistune = ["59a3429db53c50b5c6bcc8a07f8848cb00d7dc8bdb431a4ab41920d201d4756e", "88a1051873018da288eee8538d476dffe1262495144b33ecb586c4ab266bb8d4"]
 more-itertools = ["409cd48d4db7052af495b09dec721011634af3753ae1ef92d2b32f73a745f832", "92b8c4b06dac4f0611c0729b2f2ede52b2e1bac1ab48f089c7ddc12e26bb60c4"]
-mypy = ["1d98fd818ad3128a5408148c9e4a5edce6ed6b58cc314283e631dd5d9216527b", "22ee018e8fc212fe601aba65d3699689dd29a26410ef0d2cc1943de7bec7e3ac", "3a24f80776edc706ec8d05329e854d5b9e464cd332e25cde10c8da2da0a0db6c", "42a78944e80770f21609f504ca6c8173f7768043205b5ac51c9144e057dcf879", "4b2b20106973548975f0c0b1112eceb4d77ed0cafe0a231a1318f3b3a22fc795", "591a9625b4d285f3ba69f541c84c0ad9e7bffa7794da3fa0585ef13cf95cb021", "5b4b70da3d8bae73b908a90bb2c387b977e59d484d22c604a2131f6f4397c1a3", "84edda1ffeda0941b2ab38ecf49302326df79947fa33d98cdcfbf8ca9cf0bb23", "b2b83d29babd61b876ae375786960a5374bba0e4aba3c293328ca6ca5dc448dd", "cc4502f84c37223a1a5ab700649b5ab1b5e4d2bf2d426907161f20672a21930b", "e29e24dd6e7f39f200a5bb55dcaa645d38a397dd5a6674f6042ef02df5795046"]
+mypy = ["1521c186a3d200c399bd5573c828ea2db1362af7209b2adb1bb8532cea2fb36f", "31a046ab040a84a0fc38bc93694876398e62bc9f35eca8ccbf6418b7297f4c00", "3b1a411909c84b2ae9b8283b58b48541654b918e8513c20a400bb946aa9111ae", "48c8bc99380575deb39f5d3400ebb6a8a1cb5cc669bbba4d3bb30f904e0a0e7d", "540c9caa57a22d0d5d3c69047cc9dd0094d49782603eb03069821b41f9e970e9", "672e418425d957e276c291930a3921b4a6413204f53fe7c37cad7bc57b9a3391", "6ed3b9b3fdc7193ea7aca6f3c20549b377a56f28769783a8f27191903a54170f", "9371290aa2cad5ad133e4cdc43892778efd13293406f7340b9ffe99d5ec7c1d9", "ace6ac1d0f87d4072f05b5468a084a45b4eda970e4d26704f201e06d47ab2990", "b428f883d2b3fe1d052c630642cc6afddd07d5cd7873da948644508be3b9d4a7", "d5bf0e6ec8ba346a2cf35cb55bf4adfddbc6b6576fcc9e10863daa523e418dbb", "d7574e283f83c08501607586b3167728c58e8442947e027d2d4c7dcd6d82f453", "dc889c84241a857c263a2b1cd1121507db7d5b5f5e87e77147097230f374d10b", "f4748697b349f373002656bf32fede706a0e713d67bfdcf04edf39b1f61d46eb"]
 mypy-extensions = ["37e0e956f41369209a3d5f34580150bcacfabaa57b33a15c0b25f4b5725e0812", "b16cabe759f55e3409a7d231ebd2841378fb0c27a5d1994719e340e4f429ac3e"]
 nitpick = ["fb2f5f6e5c1ae8f351b0f9c01bafe68c35d87480e9bac7064cf7d15491d70db9", "ff451b41fbfe50ecda0522756a5628d6861c8c4f25c183d65bcd4efede0c8c95"]
 packaging = ["a7ac867b97fdc07ee80a8058fe4435ccd274ecc3b0ed61d852d7d53055528cf9", "c491ca87294da7cc01902edbe30a5bc6c4c28172b5138ab4e4aa1b9d7bfaeafe"]
@@ -1252,7 +1252,7 @@ testfixtures = ["665a298976c8d77f311b65c46f16b7cda7229a47dff5ad7c822e5b3371a439e
 text-unidecode = ["5a1375bb2ba7968740508ae38d92e1f889a0832913cb1c447d5e2046061a396d", "801e38bd550b943563660a91de8d4b6fa5df60a542be9093f7abf819f86050cc"]
 toml = ["229f81c57791a41d65e399fc06bf0848bab550a9dfd5ed66df18ce5f05e73d5c", "235682dd292d5899d361a811df37e04a8828a5b1da3115886b73cf81ebc9100e", "f1db651f9657708513243e61e6cc67d101a39bad662eaa9b5546f789338e07a3"]
 tomlkit = ["32c10cc16ded7e4101c79f269910658cc2a0be5913f1252121c3cd603051c269", "96e6369288571799a3052c1ef93b9de440e1ab751aa045f435b55e9d3bcd0690"]
-typed-ast = ["18511a0b3e7922276346bcb47e2ef9f38fb90fd31cb9223eed42c85d1312344e", "262c247a82d005e43b5b7f69aff746370538e176131c32dda9cb0f324d27141e", "2b907eb046d049bcd9892e3076c7a6456c93a25bebfe554e931620c90e6a25b0", "354c16e5babd09f5cb0ee000d54cfa38401d8b8891eefa878ac772f827181a3c", "4e0b70c6fc4d010f8107726af5fd37921b666f5b31d9331f0bd24ad9a088e631", "630968c5cdee51a11c05a30453f8cd65e0cc1d2ad0d9192819df9978984529f4", "66480f95b8167c9c5c5c87f32cf437d585937970f3fc24386f313a4c97b44e34", "71211d26ffd12d63a83e079ff258ac9d56a1376a25bc80b1cdcdf601b855b90b", "95bd11af7eafc16e829af2d3df510cecfd4387f6453355188342c3e79a2ec87a", "bc6c7d3fa1325a0c6613512a093bc2a2a15aeec350451cbdf9e1d4bffe3e3233", "cc34a6f5b426748a507dd5d1de4c1978f2eb5626d51326e43280941206c209e1", "d755f03c1e4a51e9b24d899561fec4ccaf51f210d52abdf8c07ee2849b212a36", "d7c45933b1bdfaf9f36c579671fec15d25b06c8398f113dab64c18ed1adda01d", "d896919306dd0aa22d0132f62a1b78d11aaf4c9fc5b3410d3c666b818191630a", "ffde2fbfad571af120fcbfbbc61c72469e72f550d676c3342492a9dfdefb8f12"]
+typed-ast = ["1170afa46a3799e18b4c977777ce137bb53c7485379d9706af8a59f2ea1aa161", "18511a0b3e7922276346bcb47e2ef9f38fb90fd31cb9223eed42c85d1312344e", "262c247a82d005e43b5b7f69aff746370538e176131c32dda9cb0f324d27141e", "2b907eb046d049bcd9892e3076c7a6456c93a25bebfe554e931620c90e6a25b0", "354c16e5babd09f5cb0ee000d54cfa38401d8b8891eefa878ac772f827181a3c", "48e5b1e71f25cfdef98b013263a88d7145879fbb2d5185f2a0c79fa7ebbeae47", "4e0b70c6fc4d010f8107726af5fd37921b666f5b31d9331f0bd24ad9a088e631", "630968c5cdee51a11c05a30453f8cd65e0cc1d2ad0d9192819df9978984529f4", "66480f95b8167c9c5c5c87f32cf437d585937970f3fc24386f313a4c97b44e34", "71211d26ffd12d63a83e079ff258ac9d56a1376a25bc80b1cdcdf601b855b90b", "7954560051331d003b4e2b3eb822d9dd2e376fa4f6d98fee32f452f52dd6ebb2", "838997f4310012cf2e1ad3803bce2f3402e9ffb71ded61b5ee22617b3a7f6b6e", "95bd11af7eafc16e829af2d3df510cecfd4387f6453355188342c3e79a2ec87a", "bc6c7d3fa1325a0c6613512a093bc2a2a15aeec350451cbdf9e1d4bffe3e3233", "cc34a6f5b426748a507dd5d1de4c1978f2eb5626d51326e43280941206c209e1", "d755f03c1e4a51e9b24d899561fec4ccaf51f210d52abdf8c07ee2849b212a36", "d7c45933b1bdfaf9f36c579671fec15d25b06c8398f113dab64c18ed1adda01d", "d896919306dd0aa22d0132f62a1b78d11aaf4c9fc5b3410d3c666b818191630a", "fdc1c9bbf79510b76408840e009ed65958feba92a88833cdceecff93ae8fff66", "ffde2fbfad571af120fcbfbbc61c72469e72f550d676c3342492a9dfdefb8f12"]
 typing = ["91dfe6f3f706ee8cc32d38edbbf304e9b7583fb37108fef38229617f8b3eba23", "c8cabb5ab8945cd2f54917be357d134db9cc1eb039e59d1606dc1e60cb1d9d36", "f38d83c5a7a7086543a0f649564d661859c5146a85775ab90c0d2f93ffaa9714"]
 typing-extensions = ["2ed632b30bb54fc3941c382decfd0ee4148f5c591651c9272473fea2c6397d95", "b1edbbf0652660e32ae780ac9433f4231e7339c7f9a8057d0f042fcbcea49b87", "d8179012ec2c620d3791ca6fe2bf7979d979acdbef1fca0bc56b37411db682ed"]
 urllib3 = ["b246607a25ac80bedac05c6f282e3cdaf3afb65420fd024ac94435cabe6e18d1", "dbe59173209418ae49d485b87d1681aefa36252ee85884c31346debd19463232"]
diff --git a/pyproject.toml b/pyproject.toml
index beb90c4..c86fca7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -57,7 +57,7 @@ flake8-pytest-style = "^0.1.3"
 nitpick = "^0.21.1"
 
 safety = "^1.8"
-mypy = "^0.730"
+mypy = "^0.740"
 
 sphinx = "^2.2"
 sphinx-readable-theme = "^1.3"