diff --git a/poetry.lock b/poetry.lock
index bf02680..6033c9e 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -123,7 +123,6 @@ pyyaml = ">=3.13"
 [[package]]
 category = "dev"
 description = "More routines for operating on iterables, beyond itertools"
-marker = "python_version < \"3.8\" or python_version > \"2.7\" or python_version >= \"3.5\" and python_version < \"3.8\""
 name = "more-itertools"
 optional = false
 python-versions = ">=3.4"
@@ -140,7 +139,7 @@ version = "0.6.2"
 [[package]]
 category = "dev"
 description = "Optional static typing for Python"
-marker = "python_version >= \"3.5\""
+marker = "python_version >= \"3.5\" and python_version < \"3.8.0b1\" or python_version >= \"3.8.0b1\""
 name = "mypy"
 optional = false
 python-versions = ">=3.5"
@@ -154,7 +153,7 @@ typing-extensions = ">=3.7.4"
 [[package]]
 category = "dev"
 description = "Experimental type system extensions for programs checked with the mypy typechecker."
-marker = "python_version >= \"3.5\""
+marker = "python_version >= \"3.5\" and python_version < \"3.8.0b1\" or python_version >= \"3.8.0b1\""
 name = "mypy-extensions"
 optional = false
 python-versions = "*"
@@ -217,27 +216,23 @@ category = "dev"
 description = "pytest: simple powerful testing with Python"
 name = "pytest"
 optional = false
-python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,>=2.7"
-version = "4.6.6"
+python-versions = ">=3.5"
+version = "5.2.1"
 
 [package.dependencies]
 atomicwrites = ">=1.0"
 attrs = ">=17.4.0"
 colorama = "*"
+more-itertools = ">=4.0.0"
 packaging = "*"
 pluggy = ">=0.12,<1.0"
 py = ">=1.5.0"
-six = ">=1.10.0"
 wcwidth = "*"
 
 [package.dependencies.importlib-metadata]
 python = "<3.8"
 version = ">=0.12"
 
-[package.dependencies.more-itertools]
-python = ">=2.8"
-version = ">=4.0.0"
-
 [[package]]
 category = "dev"
 description = "A pytest plugin to enable format checking with black"
@@ -284,13 +279,17 @@ description = "Mypy static type checker plugin for Pytest"
 name = "pytest-mypy"
 optional = false
 python-versions = "~=3.4"
-version = "0.3.3"
+version = "0.4.1"
 
 [package.dependencies]
-[package.dependencies.mypy]
-python = ">=3.5"
+[[package.dependencies.mypy]]
+python = ">=3.5,<3.8.0b1"
 version = ">=0.570"
 
+[[package.dependencies.mypy]]
+python = ">=3.8.0b1"
+version = ">=0.701"
+
 [package.dependencies.pytest]
 python = ">=3.5"
 version = ">=2.8"
@@ -356,7 +355,7 @@ version = "0.5.8"
 [[package]]
 category = "dev"
 description = "a fork of Python 2 and 3 ast modules with type comment support"
-marker = "python_version >= \"3.5\""
+marker = "python_version >= \"3.5\" and python_version < \"3.8.0b1\" or python_version >= \"3.8.0b1\""
 name = "typed-ast"
 optional = false
 python-versions = "*"
@@ -365,7 +364,7 @@ version = "1.4.0"
 [[package]]
 category = "dev"
 description = "Type Hints for Python"
-marker = "python_version >= \"3.5\""
+marker = "python_version >= \"3.5\" and python_version < \"3.8.0b1\" or python_version >= \"3.8.0b1\""
 name = "typing"
 optional = false
 python-versions = "*"
@@ -374,7 +373,7 @@ version = "3.7.4.1"
 [[package]]
 category = "dev"
 description = "Backported and Experimental Type Hints for Python 3.5+"
-marker = "python_version >= \"3.5\""
+marker = "python_version >= \"3.5\" and python_version < \"3.8.0b1\" or python_version >= \"3.8.0b1\""
 name = "typing-extensions"
 optional = false
 python-versions = "*"
@@ -420,7 +419,7 @@ version = "0.6.0"
 more-itertools = "*"
 
 [metadata]
-content-hash = "72c4874280103fcfea4584fd1d31abc3991e0454644974b53cbb84c598827b64"
+content-hash = "70c5544c4dae160d3839a28ba5f16ba102e50ede37fe163ba4e0fe2a1205d03d"
 python-versions = "^3.7"
 
 [metadata.hashes]
@@ -446,11 +445,11 @@ pluggy = ["0db4b7601aae1d35b4a033282da476845aa19185c1e6964b25cf324b5e4ec3e6", "f
 poetry-version = ["75d3f7ae3ede0539529a81170e77441bc753827f5a1de20ec8174877471d8eaf", "d0edca96a5798e668fb81cdc5941975d1cb0b6020df4b95464b2939605654617"]
 py = ["64f65755aee5b381cea27766a3a147c3f15b9b6b9ac88676de66ba2ae36793fa", "dc639b046a6e2cff5bbe40194ad65936d6ba360b52b3c3fe1d08a82dd50b5e53"]
 pyparsing = ["6f98a7b9397e206d78cc01df10131398f1c8b8510a2f4d97d9abd82e1aacdd80", "d9338df12903bbf5d65a0e4e87c2161968b10d2e489652bb47001d82a9b028b4"]
-pytest = ["5d0d20a9a66e39b5845ab14f8989f3463a7aa973700e6cdf02db69da9821e738", "692d9351353ef709c1126266579edd4fd469dcf6b5f4f583050f72161d6f3592"]
+pytest = ["7e4800063ccfc306a53c461442526c5571e1462f61583506ce97e4da6a1d88c8", "ca563435f4941d0cb34767301c27bc65c510cb82e90b9ecf9cb52dc2c63caaa0"]
 pytest-black = ["75bbeccfe23442a190164c0bf202d7498df25451fa4177b781cee20183e7fc0d"]
 pytest-cov = ["cc6742d8bac45070217169f5f72ceee1e0e55b0221f54bcf24845972d3a47f2b", "cdbdef4f870408ebdbfeb44e63e07eb18bb4619fae852f6e760645fa36172626"]
 pytest-isort = ["3be60e0de277b420ff89303ca6494320c41f7819ffa898756b90ef976e4c636a", "4bfee60dad1870b51700d55a85f5ceda766bd9d3d2878c1bbabee80e61b1be1a"]
-pytest-mypy = ["419d1d4877d41a6a80f0eb31faa7c50bb9445557f7ff1b02a1a26d10d7dc7691", "917438af835beb87f14c9f6261137f8e992b3bf87ebf73f836ac7ede03424a0f"]
+pytest-mypy = ["c01a2c3baeab6086412c614f1f92d3962ff92cdf13881c608d98a5c23bc79b77", "f6348a3aa08d7b38b05c12ed0965415e1b60d402d7ceb353f5116f6eaf7dac28"]
 pyyaml = ["0113bc0ec2ad727182326b61326afa3d1d8280ae1122493553fd6f4397f33df9", "01adf0b6c6f61bd11af6e10ca52b7d4057dd0be0343eb9283c878cf3af56aee4", "5124373960b0b3f4aa7df1707e63e9f109b5263eca5976c66e08b1c552d4eaf8", "5ca4f10adbddae56d824b2c09668e91219bb178a1eee1faa56af6f99f11bf696", "7907be34ffa3c5a32b60b95f4d95ea25361c951383a894fec31be7252b2b6f34", "7ec9b2a4ed5cad025c2278a1e6a19c011c80a3caaac804fd2d329e9cc2c287c9", "87ae4c829bb25b9fe99cf71fbb2140c448f534e24c998cc60f39ae4f94396a73", "9de9919becc9cc2ff03637872a440195ac4241c80536632fffeb6a1e25a74299", "a5a85b10e450c66b49f98846937e8cfca1db3127a9d5d1e31ca45c3d0bef4c5b", "b0997827b4f6a7c286c01c5f60384d218dca4ed7d9efa945c3e1aa623d5709ae", "b631ef96d3222e62861443cc89d6563ba3eeb816eeb96b2629345ab795e53681", "bf47c0607522fdbca6c9e817a6e81b08491de50f3766a7a0e6a5be7905961b41", "f81025eddd0327c7d4cfe9b62cf33190e1e736cc6e97502b3ec425f574b3e7a8"]
 requests = ["11e007a8a2aa0323f5a921e9e6a2d7e4e67d9877e85773fba9ba6419025cbeb4", "9cf5292fcd0f598c671cfc1e0d7d1a7f13bb8085e9a590f48c010551dc6c4b31"]
 requests-mock = ["510df890afe08d36eca5bb16b4aa6308a6f85e3159ad3013bac8b9de7bd5a010", "88d3402dd8b3c69a9e4f9d3a73ad11b15920c6efd36bc27bf1f701cf4a8e4646"]
diff --git a/pyproject.toml b/pyproject.toml
index 5baf0bc..878d845 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,10 +19,10 @@ mashumaro = "^1.7"
 poetry-version = "^0.1.3"
 
 [tool.poetry.dev-dependencies]
-pytest = "^4.6"
+pytest = "^5.0"
 pytest-black = "^0.3.7"
 pytest-cov = "^2.7"
-pytest-mypy = "^0.3.2"
+pytest-mypy = "^0.4.0"
 requests-mock = "^1.6"
 xlsxwriter = "^1.1.8"
 pytest-isort = "^0.3.1"