diff --git a/poetry.lock b/poetry.lock
index ad310c7..8b8c403 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -75,6 +75,9 @@ category = "dev"
 optional = false
 python-versions = ">=3.6"
 
+[package.dependencies]
+tomli = {version = "*", optional = true, markers = "extra == \"toml\""}
+
 [package.extras]
 toml = ["tomli"]
 
@@ -491,16 +494,15 @@ testing = ["argcomplete", "hypothesis (>=3.56)", "mock", "nose", "requests", "xm
 
 [[package]]
 name = "pytest-cov"
-version = "2.12.1"
+version = "3.0.0"
 description = "Pytest plugin for measuring coverage."
 category = "dev"
 optional = false
-python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+python-versions = ">=3.6"
 
 [package.dependencies]
-coverage = ">=5.2.1"
+coverage = {version = ">=5.2.1", extras = ["toml"]}
 pytest = ">=4.6"
-toml = "*"
 
 [package.extras]
 testing = ["fields", "hunter", "process-tests", "six", "pytest-xdist", "virtualenv"]
@@ -626,6 +628,14 @@ category = "dev"
 optional = false
 python-versions = ">=2.6, !=3.0.*, !=3.1.*, !=3.2.*"
 
+[[package]]
+name = "tomli"
+version = "1.2.1"
+description = "A lil' TOML parser"
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
 [[package]]
 name = "typing-extensions"
 version = "3.10.0.2"
@@ -657,7 +667,7 @@ testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytes
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7.0"
-content-hash = "807e5bc2e19b0af225742fa0efc0c1035622c60bcb9c839c927a86954d93c9dc"
+content-hash = "fd1d32666ba862f5405c08c9afbdcf36a43f346187b5bca07b0c28d4b2bd3301"
 
 [metadata.files]
 anyconfig = [
@@ -928,8 +938,8 @@ pytest = [
     {file = "pytest-6.2.5.tar.gz", hash = "sha256:131b36680866a76e6781d13f101efb86cf674ebb9762eb70d3082b6f29889e89"},
 ]
 pytest-cov = [
-    {file = "pytest-cov-2.12.1.tar.gz", hash = "sha256:261ceeb8c227b726249b376b8526b600f38667ee314f910353fa318caa01f4d7"},
-    {file = "pytest_cov-2.12.1-py2.py3-none-any.whl", hash = "sha256:261bb9e47e65bd099c89c3edf92972865210c36813f80ede5277dceb77a4a62a"},
+    {file = "pytest-cov-3.0.0.tar.gz", hash = "sha256:e7f0f5b1617d2210a2cabc266dfe2f4c75a8d32fb89eafb7ad9d06f6d076d470"},
+    {file = "pytest_cov-3.0.0-py3-none-any.whl", hash = "sha256:578d5d15ac4a25e5f961c938b85a05b09fdaae9deef3bb6de9a6e766622ca7a6"},
 ]
 pytest-mock = [
     {file = "pytest-mock-3.6.1.tar.gz", hash = "sha256:40217a058c52a63f1042f0784f62009e976ba824c418cced42e88d5f40ab0e62"},
@@ -1025,6 +1035,10 @@ toml = [
     {file = "toml-0.10.2-py2.py3-none-any.whl", hash = "sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b"},
     {file = "toml-0.10.2.tar.gz", hash = "sha256:b3bda1d108d5dd99f4a20d24d9c348e91c4db7ab1b749200bded2f839ccbe68f"},
 ]
+tomli = [
+    {file = "tomli-1.2.1-py3-none-any.whl", hash = "sha256:8dd0e9524d6f386271a36b41dbf6c57d8e32fd96fd22b6584679dc569d20899f"},
+    {file = "tomli-1.2.1.tar.gz", hash = "sha256:a5b75cb6f3968abb47af1b40c1819dc519ea82bcc065776a866e8d74c5ca9442"},
+]
 typing-extensions = [
     {file = "typing_extensions-3.10.0.2-py2-none-any.whl", hash = "sha256:d8226d10bc02a29bcc81df19a26e56a9647f8b0a6d4a83924139f4a8b01f17b7"},
     {file = "typing_extensions-3.10.0.2-py3-none-any.whl", hash = "sha256:f1d25edafde516b146ecd0613dabcc61409817af4766fbbcfb8d1ad4ec441a34"},
diff --git a/pyproject.toml b/pyproject.toml
index eab1649..6400a23 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -61,7 +61,7 @@ flake8-quotes = "3.3.0"
 pep8-naming = "0.12.1"
 pydocstyle = "6.1.1"
 pytest = "6.2.5"
-pytest-cov = "2.12.1"
+pytest-cov = "3.0.0"
 pytest-mock = "3.6.1"
 yapf = "0.31.0"