diff --git a/poetry.lock b/poetry.lock
index b16cf9e..7ee7efc 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -80,16 +80,16 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 
 [[package]]
 name = "graphviz"
-version = "0.19.1"
+version = "0.20.1"
 description = "Simple Python interface for Graphviz"
 category = "main"
 optional = false
-python-versions = ">=3.6"
+python-versions = ">=3.7"
 
 [package.extras]
 dev = ["flake8", "pep8-naming", "tox (>=3)", "twine", "wheel"]
-docs = ["sphinx (>=1.8)", "sphinx-autodoc-typehints", "sphinx-rtd-theme"]
-test = ["coverage", "mock (>=4)", "pytest (>=6)", "pytest-cov", "pytest-mock (>=3)"]
+docs = ["sphinx (>=5)", "sphinx-autodoc-typehints", "sphinx-rtd-theme"]
+test = ["coverage", "mock (>=4)", "pytest (>=7)", "pytest-cov", "pytest-mock (>=3)"]
 
 [[package]]
 name = "importlib-metadata"
@@ -349,7 +349,7 @@ testing = ["func-timeout", "jaraco.itertools"]
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7"
-content-hash = "424f1037b46d65e63b58808fe626a8792180ea4b543bda912865828621ae7892"
+content-hash = "f4720113cecfd062af43fa97a1e62a2c47041fde53df3e19fc50516c34d1abe8"
 
 [metadata.files]
 astroid = [
@@ -387,8 +387,8 @@ colorama = [
     {file = "colorama-0.4.3.tar.gz", hash = "sha256:e96da0d330793e2cb9485e9ddfd918d456036c7149416295932478192f4436a1"},
 ]
 graphviz = [
-    {file = "graphviz-0.19.1-py3-none-any.whl", hash = "sha256:f34088c08be2ec16279dfa9c3b4ff3d1453c5c67597a33e2819b000e18d4c546"},
-    {file = "graphviz-0.19.1.zip", hash = "sha256:09ed0cde452d015fe77c4845a210eb642f28d245f5bc250d4b97808cb8f49078"},
+    {file = "graphviz-0.20.1-py3-none-any.whl", hash = "sha256:587c58a223b51611c0cf461132da386edd896a029524ca61a1462b880bf97977"},
+    {file = "graphviz-0.20.1.zip", hash = "sha256:8c58f14adaa3b947daf26c19bc1e98c4e0702cdc31cf99153e6f06904d492bf8"},
 ]
 importlib-metadata = [
     {file = "importlib_metadata-1.5.0-py2.py3-none-any.whl", hash = "sha256:b97607a1a18a5100839aec1dc26a1ea17ee0d93b20b0f008d80a5a050afb200b"},
diff --git a/pyproject.toml b/pyproject.toml
index 654599d..b237457 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -11,7 +11,7 @@ include = ["resources/**/*"]
 
 [tool.poetry.dependencies]
 python = "^3.7"
-graphviz = ">=0.13.2,<0.20.0"
+graphviz = ">=0.13.2,<0.21.0"
 jinja2 = ">=2.10,<4.0"
 contextvars = { version = "^2.4", python = "~3.6" }
 typed-ast = "^1.5.4"