diff --git a/poetry.lock b/poetry.lock
index e1b1883..e27740a 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -60,7 +60,7 @@ python-versions = ">=2.6, !=3.0.*, !=3.1.*, !=3.2.*, <4"
 version = "4.5.3"
 
 [[package]]
-category = "dev"
+category = "main"
 description = "Discover and load entry points from installed packages."
 name = "entrypoints"
 optional = false
@@ -68,7 +68,7 @@ python-versions = ">=2.7"
 version = "0.3"
 
 [[package]]
-category = "dev"
+category = "main"
 description = "the modular source code checker: pep8, pyflakes and co"
 name = "flake8"
 optional = false
@@ -205,12 +205,12 @@ version = "2.0.1"
 flake8 = "*"
 
 [[package]]
-category = "dev"
+category = "main"
 description = "Check code for 1 element tuple."
 name = "flake8-tuple"
 optional = false
 python-versions = "*"
-version = "0.3.1"
+version = "0.4.0"
 
 [package.dependencies]
 flake8 = "*"
@@ -236,7 +236,7 @@ version = "0.17"
 zipp = ">=0.5"
 
 [[package]]
-category = "dev"
+category = "main"
 description = "McCabe checker, plugin for flake8"
 name = "mccabe"
 optional = false
@@ -295,7 +295,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "1.8.0"
 
 [[package]]
-category = "dev"
+category = "main"
 description = "Python style guide checker"
 name = "pycodestyle"
 optional = false
@@ -303,7 +303,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "2.5.0"
 
 [[package]]
-category = "dev"
+category = "main"
 description = "passive checker of Python programs"
 name = "pyflakes"
 optional = false
@@ -368,7 +368,7 @@ idna = ">=2.5,<2.9"
 urllib3 = ">=1.21.1,<1.25.0 || >1.25.0,<1.25.1 || >1.25.1,<1.26"
 
 [[package]]
-category = "dev"
+category = "main"
 description = "Python 2 and 3 compatibility utilities"
 name = "six"
 optional = false
@@ -400,7 +400,7 @@ python-versions = ">=2.7"
 version = "0.5.1"
 
 [metadata]
-content-hash = "8557d8a6c6e02a3f9ff278ef4b551ecb211cc5a0921803105ed8271ae17e82a6"
+content-hash = "51823ede3b856413a910205dadd6c4a865a9869a5144b290551f0d45159301ee"
 python-versions = "==3.7.*"
 
 [metadata.hashes]
@@ -424,7 +424,7 @@ flake8-import-order = ["90a80e46886259b9c396b578d75c749801a41ee969a235e163cfe1be
 flake8-mutable = ["38fd9dadcbcda6550a916197bc40ed76908119dabb37fbcca30873666c31d2d5", "ee9b77111b867d845177bbc289d87d541445ffcc6029a0c5c65865b42b18c6a6"]
 flake8-polyfill = ["12be6a34ee3ab795b19ca73505e7b55826d5f6ad7230d31b18e106400169b9e9", "e44b087597f6da52ec6393a709e7108b2905317d0c0b744cdca6208e670d8eda"]
 flake8-quotes = ["10c9af6b472d4302a8e721c5260856c3f985c5c082b04841aefd2f808ac02038"]
-flake8-tuple = ["81b16bc753616d7940275951f69db4cd8c6afafca00eb5767942215c9e455075"]
+flake8-tuple = ["8d41db2e4a5320ffd29cf78a95f1d7da9f22b47949427a4d7f8391333eec2a15"]
 idna = ["c357b3f628cf53ae2c4c05627ecc484553142ca23264e593d327bcde5e9c3407", "ea8b7f6188e6fa117537c3df7da9fc686d485087abf6ac197f9c46432f7e4a3c"]
 importlib-metadata = ["a9f185022cfa69e9ca5f7eabfd5a58b689894cb78a11e3c8c89398a8ccbb8e7f", "df1403cd3aebeb2b1dcd3515ca062eecb5bd3ea7611f18cba81130c68707e879"]
 mccabe = ["ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42", "dd8d182285a0fe56bace7f45b5e7d1a6ebcbf524e8f3bd87eb0f125271b8831f"]
diff --git a/pyproject.toml b/pyproject.toml
index 546f64c..9172284 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -21,6 +21,7 @@ classifiers=[
 
 [tool.poetry.dependencies]
 python = "==3.7.*"
+flake8-tuple = "^0.4.0"
 
 [tool.poetry.dev-dependencies]
 flake8 = "^3.7"
@@ -31,7 +32,6 @@ flake8-deprecated = "^1.3"
 flake8-mutable = "^1.2"
 flake8-builtins = "^1.4"
 flake8-bugbear = "^19.3"
-flake8-tuple = "^0.3.1"
 flake8-blind-except = "^0.1.1"
 flake8-class-newline = "^1.6"
 flake8-import-order = "^0.18.1"