diff --git a/poetry.lock b/poetry.lock
index e16f213..b4853c8 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -637,7 +637,7 @@ toml = "*"
 
 [[package]]
 name = "tox"
-version = "3.19.0"
+version = "3.23.1"
 description = "tox is a generic virtualenv management and test command line tool"
 category = "dev"
 optional = false
@@ -646,7 +646,7 @@ python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,>=2.7"
 [package.dependencies]
 colorama = {version = ">=0.4.1", markers = "platform_system == \"Windows\""}
 filelock = ">=3.0.0"
-importlib-metadata = {version = ">=0.12,<2", markers = "python_version < \"3.8\""}
+importlib-metadata = {version = ">=0.12", markers = "python_version < \"3.8\""}
 packaging = ">=14"
 pluggy = ">=0.12.0"
 py = ">=1.4.17"
@@ -656,7 +656,7 @@ virtualenv = ">=16.0.0,<20.0.0 || >20.0.0,<20.0.1 || >20.0.1,<20.0.2 || >20.0.2,
 
 [package.extras]
 docs = ["pygments-github-lexers (>=0.0.5)", "sphinx (>=2.0.0)", "sphinxcontrib-autoprogram (>=0.1.5)", "towncrier (>=18.5.0)"]
-testing = ["flaky (>=3.4.0)", "freezegun (>=0.3.11)", "pathlib2 (>=2.3.3)", "psutil (>=5.6.1)", "pytest (>=4.0.0)", "pytest-cov (>=2.5.1)", "pytest-mock (>=1.10.0)", "pytest-randomly (>=1.0.0)", "pytest-xdist (>=1.22.2)"]
+testing = ["flaky (>=3.4.0)", "freezegun (>=0.3.11)", "psutil (>=5.6.1)", "pytest (>=4.0.0)", "pytest-cov (>=2.5.1)", "pytest-mock (>=1.10.0)", "pytest-randomly (>=1.0.0)", "pytest-xdist (>=1.22.2)", "pathlib2 (>=2.3.3)"]
 
 [[package]]
 name = "urllib3"
@@ -703,7 +703,7 @@ travis-ci = []
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.6"
-content-hash = "a18078e1b4a0363f1c0171e88d27f24b80e5a9e8d460836525b282702be6458f"
+content-hash = "11bdd29f52c9b13073b8167602016e2390448859d3ceb895a40c6233300a65b6"
 
 [metadata.files]
 alabaster = [
@@ -1025,8 +1025,8 @@ towncrier = [
     {file = "towncrier-19.2.0.tar.gz", hash = "sha256:48251a1ae66d2cf7e6fa5552016386831b3e12bb3b2d08eb70374508c17a8196"},
 ]
 tox = [
-    {file = "tox-3.19.0-py2.py3-none-any.whl", hash = "sha256:3d94b6921a0b6dc90fd8128df83741f30bb41ccd6cd52d131a6a6944ca8f16e6"},
-    {file = "tox-3.19.0.tar.gz", hash = "sha256:17e61a93afe5c49281fb969ab71f7a3f22d7586d1c56f9a74219910f356fe7d3"},
+    {file = "tox-3.23.1-py2.py3-none-any.whl", hash = "sha256:b0b5818049a1c1997599d42012a637a33f24c62ab8187223fdd318fa8522637b"},
+    {file = "tox-3.23.1.tar.gz", hash = "sha256:307a81ddb82bd463971a273f33e9533a24ed22185f27db8ce3386bff27d324e3"},
 ]
 urllib3 = [
     {file = "urllib3-1.24.2-py2.py3-none-any.whl", hash = "sha256:4c291ca23bbb55c76518905869ef34bdd5f0e46af7afe6861e8375643ffee1a0"},
diff --git a/pyproject.toml b/pyproject.toml
index 7a5815f..ec3e258 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,7 +39,7 @@ pytest-flake8 = "^1.0"
 responses = "^0.10.15"
 pytest-runner = "^5.3"
 towncrier = {version = "^19.2", optional = true}
-tox = "^3.19"
+tox = "^3.23"
 sphinx = {version = "^3.1", optional = true}
 sphinx_rtd_theme = {version = "^0.5.0", optional = true}
 pre-commit = {version = "^2.1", optional = true}