diff --git a/poetry.lock b/poetry.lock
index 5ebaf43..3bea0af 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -81,17 +81,17 @@ python-versions = ">=2.6, !=3.0.*, !=3.1.*"
 
 [[package]]
 name = "flake8"
-version = "3.8.4"
+version = "3.9.0"
 description = "the modular source code checker: pep8 pyflakes and co"
 category = "dev"
 optional = false
-python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,>=2.7"
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,>=2.7"
 
 [package.dependencies]
 importlib-metadata = {version = "*", markers = "python_version < \"3.8\""}
 mccabe = ">=0.6.0,<0.7.0"
-pycodestyle = ">=2.6.0a1,<2.7.0"
-pyflakes = ">=2.2.0,<2.3.0"
+pycodestyle = ">=2.7.0,<2.8.0"
+pyflakes = ">=2.3.0,<2.4.0"
 
 [[package]]
 name = "importlib-metadata"
@@ -316,7 +316,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [[package]]
 name = "pycodestyle"
-version = "2.6.0"
+version = "2.7.0"
 description = "Python style guide checker"
 category = "dev"
 optional = false
@@ -335,7 +335,7 @@ click = ">=4.1"
 
 [[package]]
 name = "pyflakes"
-version = "2.2.0"
+version = "2.3.0"
 description = "passive checker of Python programs"
 category = "dev"
 optional = false
@@ -478,7 +478,7 @@ testing = ["pytest (>=3.5,!=3.7.3)", "pytest-checkdocs (>=1.2.3)", "pytest-flake
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.6"
-content-hash = "6c81df97f71df0b1943655e63d79845dcb957d48e390c067572e15532c6f6b20"
+content-hash = "c9f0b0d7be075770dbf4596de92cf4e3bbd9eebf1b2ca730d6dd83d617dafc09"
 
 [metadata.files]
 appnope = [
@@ -565,8 +565,8 @@ decorator = [
     {file = "decorator-4.4.2.tar.gz", hash = "sha256:e3a62f0520172440ca0dcc823749319382e377f37f140a0b99ef45fecb84bfe7"},
 ]
 flake8 = [
-    {file = "flake8-3.8.4-py2.py3-none-any.whl", hash = "sha256:749dbbd6bfd0cf1318af27bf97a14e28e5ff548ef8e5b1566ccfb25a11e7c839"},
-    {file = "flake8-3.8.4.tar.gz", hash = "sha256:aadae8761ec651813c24be05c6f7b4680857ef6afaae4651a4eccaef97ce6c3b"},
+    {file = "flake8-3.9.0-py2.py3-none-any.whl", hash = "sha256:12d05ab02614b6aee8df7c36b97d1a3b2372761222b19b58621355e82acddcff"},
+    {file = "flake8-3.9.0.tar.gz", hash = "sha256:78873e372b12b093da7b5e5ed302e8ad9e988b38b063b61ad937f26ca58fc5f0"},
 ]
 importlib-metadata = [
     {file = "importlib_metadata-3.4.0-py3-none-any.whl", hash = "sha256:ace61d5fc652dc280e7b6b4ff732a9c2d40db2c0f92bc6cb74e07b73d53a1771"},
@@ -660,16 +660,16 @@ py = [
     {file = "py-1.10.0.tar.gz", hash = "sha256:21b81bda15b66ef5e1a777a21c4dcd9c20ad3efd0b3f817e7a809035269e1bd3"},
 ]
 pycodestyle = [
-    {file = "pycodestyle-2.6.0-py2.py3-none-any.whl", hash = "sha256:2295e7b2f6b5bd100585ebcb1f616591b652db8a741695b3d8f5d28bdc934367"},
-    {file = "pycodestyle-2.6.0.tar.gz", hash = "sha256:c58a7d2815e0e8d7972bf1803331fb0152f867bd89adf8a01dfd55085434192e"},
+    {file = "pycodestyle-2.7.0-py2.py3-none-any.whl", hash = "sha256:514f76d918fcc0b55c6680472f0a37970994e07bbb80725808c17089be302068"},
+    {file = "pycodestyle-2.7.0.tar.gz", hash = "sha256:c389c1d06bf7904078ca03399a4816f974a1d590090fecea0c63ec26ebaf1cef"},
 ]
 pyemojify = [
     {file = "pyemojify-0.2.0-py2.py3-none-any.whl", hash = "sha256:e70e4cfcfe0aed7b5bc64f39b023d5d62a5f5c0c31c1b7114cd43a059fb14a72"},
     {file = "pyemojify-0.2.0.tar.gz", hash = "sha256:6bbc3c8d52e3df3e4039bc0cad3616d3eb579b4c6e15a11bd5e0ef0d579596a9"},
 ]
 pyflakes = [
-    {file = "pyflakes-2.2.0-py2.py3-none-any.whl", hash = "sha256:0d94e0e05a19e57a99444b6ddcf9a6eb2e5c68d3ca1e98e90707af8152c90a92"},
-    {file = "pyflakes-2.2.0.tar.gz", hash = "sha256:35b2d75ee967ea93b55750aa9edbbf72813e06a66ba54438df2cfac9e3c27fc8"},
+    {file = "pyflakes-2.3.0-py2.py3-none-any.whl", hash = "sha256:910208209dcea632721cb58363d0f72913d9e8cf64dc6f8ae2e02a3609aba40d"},
+    {file = "pyflakes-2.3.0.tar.gz", hash = "sha256:e59fd8e750e588358f1b8885e5a4751203a0516e0ee6d34811089ac294c8806f"},
 ]
 pygments = [
     {file = "Pygments-2.7.4-py3-none-any.whl", hash = "sha256:bc9591213a8f0e0ca1a5e68a479b4887fdc3e75d0774e5c71c31920c427de435"},
diff --git a/pyproject.toml b/pyproject.toml
index 068d454..092322f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,7 +34,7 @@ pygments = "^2.5.2"
 [tool.poetry.dev-dependencies]
 ipdb = "^0.13.2"
 mypy = "^0.812"
-flake8 = "^3.8.3"
+flake8 = "^3.9.0"
 pytest = "^5.4.3"
 pytest-cov = "^2.10.0"