diff --git a/poetry.lock b/poetry.lock
index 2fdcf011..d8234c14 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -174,9 +174,9 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 
 [[package]]
 name = "importlib-metadata"
-version = "3.3.0"
+version = "4.8.3"
 description = "Read metadata from Python packages"
-category = "dev"
+category = "main"
 optional = false
 python-versions = ">=3.6"
 
@@ -185,8 +185,9 @@ typing-extensions = {version = ">=3.6.4", markers = "python_version < \"3.8\""}
 zipp = ">=0.5"
 
 [package.extras]
-docs = ["sphinx", "jaraco.packaging (>=3.2)", "rst.linker (>=1.9)"]
-testing = ["pytest (>=3.5,!=3.7.3)", "pytest-checkdocs (>=1.2.3)", "pytest-flake8", "pytest-cov", "jaraco.test (>=3.2.0)", "packaging", "pep517", "pyfakefs", "flufl.flake8", "pytest-black (>=0.3.7)", "pytest-mypy", "importlib-resources (>=1.3)"]
+docs = ["sphinx", "jaraco.packaging (>=8.2)", "rst.linker (>=1.9)"]
+perf = ["ipython"]
+testing = ["pytest (>=6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-cov", "pytest-enabler (>=1.0.1)", "packaging", "pep517", "pyfakefs", "flufl.flake8", "pytest-perf (>=0.9.2)", "pytest-black (>=0.3.7)", "pytest-mypy", "importlib-resources (>=1.3)"]
 
 [[package]]
 name = "iniconfig"
@@ -367,7 +368,7 @@ coverage = {version = ">=5.2.1", extras = ["toml"]}
 pytest = ">=4.6"
 
 [package.extras]
-testing = ["fields", "hunter", "process-tests", "six", "pytest-xdist", "virtualenv"]
+testing = ["virtualenv", "pytest-xdist", "six", "process-tests", "hunter", "fields"]
 
 [[package]]
 name = "pytest-pycodestyle"
@@ -436,18 +437,19 @@ python-versions = "*"
 
 [[package]]
 name = "sphinx"
-version = "3.4.0"
+version = "5.1.1"
 description = "Python documentation generator"
 category = "main"
 optional = true
-python-versions = ">=3.5"
+python-versions = ">=3.6"
 
 [package.dependencies]
 alabaster = ">=0.7,<0.8"
 babel = ">=1.3"
 colorama = {version = ">=0.3.5", markers = "sys_platform == \"win32\""}
-docutils = ">=0.12"
+docutils = ">=0.14,<0.20"
 imagesize = "*"
+importlib-metadata = {version = ">=4.4", markers = "python_version < \"3.10\""}
 Jinja2 = ">=2.3"
 packaging = "*"
 Pygments = ">=2.0"
@@ -455,15 +457,15 @@ requests = ">=2.5.0"
 snowballstemmer = ">=1.1"
 sphinxcontrib-applehelp = "*"
 sphinxcontrib-devhelp = "*"
-sphinxcontrib-htmlhelp = "*"
+sphinxcontrib-htmlhelp = ">=2.0.0"
 sphinxcontrib-jsmath = "*"
 sphinxcontrib-qthelp = "*"
-sphinxcontrib-serializinghtml = "*"
+sphinxcontrib-serializinghtml = ">=1.1.5"
 
 [package.extras]
 docs = ["sphinxcontrib-websupport"]
-lint = ["flake8 (>=3.5.0)", "isort", "mypy (>=0.790)", "docutils-stubs"]
-test = ["pytest", "pytest-cov", "html5lib", "cython", "typed-ast"]
+lint = ["flake8 (>=3.5.0)", "flake8-comprehensions", "flake8-bugbear", "isort", "mypy (>=0.971)", "sphinx-lint", "docutils-stubs", "types-typed-ast", "types-requests"]
+test = ["pytest (>=4.6)", "html5lib", "cython", "typed-ast"]
 
 [[package]]
 name = "sphinx-autobuild"
@@ -508,8 +510,8 @@ python-versions = ">=3.6"
 sphinx = ">=1.8"
 
 [package.extras]
+rtd = ["sphinx-book-theme", "ipython", "sphinx"]
 code_style = ["pre-commit (==2.12.1)"]
-rtd = ["sphinx", "ipython", "sphinx-book-theme"]
 
 [[package]]
 name = "sphinx-rtd-theme"
@@ -524,7 +526,7 @@ docutils = "<0.17"
 sphinx = "*"
 
 [package.extras]
-dev = ["transifex-client", "sphinxcontrib-httpdomain", "bump2version"]
+dev = ["bump2version", "sphinxcontrib-httpdomain", "transifex-client"]
 
 [[package]]
 name = "sphinxcontrib-applehelp"
@@ -535,8 +537,8 @@ optional = true
 python-versions = ">=3.5"
 
 [package.extras]
-lint = ["flake8", "mypy", "docutils-stubs"]
 test = ["pytest"]
+lint = ["docutils-stubs", "mypy", "flake8"]
 
 [[package]]
 name = "sphinxcontrib-devhelp"
@@ -547,20 +549,20 @@ optional = true
 python-versions = ">=3.5"
 
 [package.extras]
-lint = ["flake8", "mypy", "docutils-stubs"]
 test = ["pytest"]
+lint = ["docutils-stubs", "mypy", "flake8"]
 
 [[package]]
 name = "sphinxcontrib-htmlhelp"
-version = "1.0.3"
+version = "2.0.0"
 description = "sphinxcontrib-htmlhelp is a sphinx extension which renders HTML help files"
 category = "main"
 optional = true
-python-versions = ">=3.5"
+python-versions = ">=3.6"
 
 [package.extras]
-lint = ["flake8", "mypy", "docutils-stubs"]
-test = ["pytest", "html5lib"]
+test = ["html5lib", "pytest"]
+lint = ["docutils-stubs", "mypy", "flake8"]
 
 [[package]]
 name = "sphinxcontrib-jsmath"
@@ -571,7 +573,7 @@ optional = true
 python-versions = ">=3.5"
 
 [package.extras]
-test = ["pytest", "flake8", "mypy"]
+test = ["mypy", "flake8", "pytest"]
 
 [[package]]
 name = "sphinxcontrib-qthelp"
@@ -582,12 +584,12 @@ optional = true
 python-versions = ">=3.5"
 
 [package.extras]
-lint = ["flake8", "mypy", "docutils-stubs"]
 test = ["pytest"]
+lint = ["docutils-stubs", "mypy", "flake8"]
 
 [[package]]
 name = "sphinxcontrib-serializinghtml"
-version = "1.1.4"
+version = "1.1.5"
 description = "sphinxcontrib-serializinghtml is a sphinx extension which outputs \"serialized\" HTML files (json and pickle)."
 category = "main"
 optional = true
@@ -625,7 +627,7 @@ python-versions = "*"
 name = "typing-extensions"
 version = "3.7.4.3"
 description = "Backported and Experimental Type Hints for Python 3.5+"
-category = "dev"
+category = "main"
 optional = false
 python-versions = "*"
 
@@ -654,7 +656,7 @@ python-versions = "*"
 name = "zipp"
 version = "3.4.0"
 description = "Backport of pathlib-compatible object wrapper for zip files"
-category = "dev"
+category = "main"
 optional = false
 python-versions = ">=3.6"
 
@@ -668,7 +670,7 @@ docs = ["Sphinx", "sphinx-rtd-theme", "sphinx-autobuild", "sphinx-copybutton", "
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.6"
-content-hash = "d48d5d7c9a4b0ebf22a3d980582be96131c2420606570a074b98f3823b6af17b"
+content-hash = "41da439476da9cabd53769c49d49ee6dffb9fd6e2654b8f3c1234ee6191cd5bb"
 
 [metadata.files]
 alabaster = [
@@ -785,8 +787,8 @@ imagesize = [
     {file = "imagesize-1.2.0.tar.gz", hash = "sha256:b1f6b5a4eab1f73479a50fb79fcf729514a900c341d8503d62a62dbc4127a2b1"},
 ]
 importlib-metadata = [
-    {file = "importlib_metadata-3.3.0-py3-none-any.whl", hash = "sha256:bf792d480abbd5eda85794e4afb09dd538393f7d6e6ffef6e9f03d2014cf9450"},
-    {file = "importlib_metadata-3.3.0.tar.gz", hash = "sha256:5c5a2720817414a6c41f0a49993908068243ae02c1635a228126519b509c8aed"},
+    {file = "importlib_metadata-4.8.3-py3-none-any.whl", hash = "sha256:65a9576a5b2d58ca44d133c42a241905cc45e34d2c06fd5ba2bafa221e5d7b5e"},
+    {file = "importlib_metadata-4.8.3.tar.gz", hash = "sha256:766abffff765960fcc18003801f7044eb6755ffae4521c8e8ce8e83b9c9b0668"},
 ]
 iniconfig = [
     {file = "iniconfig-1.1.1-py2.py3-none-any.whl", hash = "sha256:011e24c64b7f47f6ebd835bb12a743f2fbe9a26d4cecaa7f53bc4f35ee9da8b3"},
@@ -985,8 +987,8 @@ snowballstemmer = [
     {file = "snowballstemmer-2.0.0.tar.gz", hash = "sha256:df3bac3df4c2c01363f3dd2cfa78cce2840a79b9f1c2d2de9ce8d31683992f52"},
 ]
 sphinx = [
-    {file = "Sphinx-3.4.0-py3-none-any.whl", hash = "sha256:77c801947eb86457822e01eadd5c2e2de020db0201f1f9fc98b0927980b6d212"},
-    {file = "Sphinx-3.4.0.tar.gz", hash = "sha256:4dcde313801f23ea4789ac31e5405e240cb758b5d375804807f2f3cc3c396bfa"},
+    {file = "Sphinx-5.1.1-py3-none-any.whl", hash = "sha256:309a8da80cb6da9f4713438e5b55861877d5d7976b69d87e336733637ea12693"},
+    {file = "Sphinx-5.1.1.tar.gz", hash = "sha256:ba3224a4e206e1fbdecf98a4fae4992ef9b24b85ebf7b584bb340156eaf08d89"},
 ]
 sphinx-autobuild = [
     {file = "sphinx-autobuild-2021.3.14.tar.gz", hash = "sha256:de1ca3b66e271d2b5b5140c35034c89e47f263f2cd5db302c9217065f7443f05"},
@@ -1013,8 +1015,8 @@ sphinxcontrib-devhelp = [
     {file = "sphinxcontrib_devhelp-1.0.2-py2.py3-none-any.whl", hash = "sha256:8165223f9a335cc1af7ffe1ed31d2871f325254c0423bc0c4c7cd1c1e4734a2e"},
 ]
 sphinxcontrib-htmlhelp = [
-    {file = "sphinxcontrib-htmlhelp-1.0.3.tar.gz", hash = "sha256:e8f5bb7e31b2dbb25b9cc435c8ab7a79787ebf7f906155729338f3156d93659b"},
-    {file = "sphinxcontrib_htmlhelp-1.0.3-py2.py3-none-any.whl", hash = "sha256:3c0bc24a2c41e340ac37c85ced6dafc879ab485c095b1d65d2461ac2f7cca86f"},
+    {file = "sphinxcontrib-htmlhelp-2.0.0.tar.gz", hash = "sha256:f5f8bb2d0d629f398bf47d0d69c07bc13b65f75a81ad9e2f71a63d4b7a2f6db2"},
+    {file = "sphinxcontrib_htmlhelp-2.0.0-py2.py3-none-any.whl", hash = "sha256:d412243dfb797ae3ec2b59eca0e52dac12e75a241bf0e4eb861e450d06c6ed07"},
 ]
 sphinxcontrib-jsmath = [
     {file = "sphinxcontrib-jsmath-1.0.1.tar.gz", hash = "sha256:a9925e4a4587247ed2191a22df5f6970656cb8ca2bd6284309578f2153e0c4b8"},
@@ -1025,8 +1027,8 @@ sphinxcontrib-qthelp = [
     {file = "sphinxcontrib_qthelp-1.0.3-py2.py3-none-any.whl", hash = "sha256:bd9fc24bcb748a8d51fd4ecaade681350aa63009a347a8c14e637895444dfab6"},
 ]
 sphinxcontrib-serializinghtml = [
-    {file = "sphinxcontrib-serializinghtml-1.1.4.tar.gz", hash = "sha256:eaa0eccc86e982a9b939b2b82d12cc5d013385ba5eadcc7e4fed23f4405f77bc"},
-    {file = "sphinxcontrib_serializinghtml-1.1.4-py2.py3-none-any.whl", hash = "sha256:f242a81d423f59617a8e5cf16f5d4d74e28ee9a66f9e5b637a18082991db5a9a"},
+    {file = "sphinxcontrib-serializinghtml-1.1.5.tar.gz", hash = "sha256:aa5f6de5dfdf809ef505c4895e51ef5c9eac17d0f287933eb49ec495280b6952"},
+    {file = "sphinxcontrib_serializinghtml-1.1.5-py2.py3-none-any.whl", hash = "sha256:352a9a00ae864471d3a7ead8d7d79f5fc0b57e8b3f95e9867eb9eb28999b92fd"},
 ]
 toml = [
     {file = "toml-0.10.2-py2.py3-none-any.whl", hash = "sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b"},
diff --git a/pyproject.toml b/pyproject.toml
index 4016454f..c759edc2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,7 +34,7 @@ license = "MIT"
 [tool.poetry.dependencies]
 python = "^3.6"
 prompt_toolkit = ">=2.0,<4.0"
-Sphinx = {version = "^3.3", optional = true}
+Sphinx = {version = ">=3.3,<6.0", optional = true}
 sphinx-rtd-theme = {version = "^0.5.0", optional = true}
 sphinx-autobuild = {version = ">=2020.9.1,<2022.0.0", optional = true}
 sphinx-copybutton = {version = ">=0.3.1,<0.5.0", optional = true}