diff --git a/poetry.lock b/poetry.lock
index 21dfe2e..3edfc54 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -57,25 +57,26 @@ tests_no_zope = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>
 
 [[package]]
 name = "black"
-version = "20.8b1"
+version = "21.4b2"
 description = "The uncompromising code formatter."
 category = "dev"
 optional = false
-python-versions = ">=3.6"
+python-versions = ">=3.6.2"
 
 [package.dependencies]
 appdirs = "*"
 click = ">=7.1.2"
 mypy-extensions = ">=0.4.3"
-pathspec = ">=0.6,<1"
+pathspec = ">=0.8.1,<1"
 regex = ">=2020.1.8"
 toml = ">=0.10.1"
-typed-ast = ">=1.4.0"
-typing-extensions = ">=3.7.4"
+typed-ast = {version = ">=1.4.2", markers = "python_version < \"3.8\""}
+typing-extensions = {version = ">=3.7.4", markers = "python_version < \"3.8\""}
 
 [package.extras]
 colorama = ["colorama (>=0.4.3)"]
 d = ["aiohttp (>=3.3.2)", "aiohttp-cors"]
+python2 = ["typed-ast (>=1.4.2)"]
 
 [[package]]
 name = "certifi"
@@ -296,7 +297,7 @@ six = "*"
 
 [[package]]
 name = "pathspec"
-version = "0.8.0"
+version = "0.8.1"
 description = "Utility library for gitignore style pattern matching of file paths."
 category = "dev"
 optional = false
@@ -531,7 +532,7 @@ python-versions = "*"
 
 [[package]]
 name = "typed-ast"
-version = "1.4.1"
+version = "1.4.3"
 description = "a fork of Python 2 and 3 ast modules with type comment support"
 category = "dev"
 optional = false
@@ -593,7 +594,7 @@ sqlite = ["aiosqlite"]
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7"
-content-hash = "bfc111f9cfcf8137c21116a4deec59b237eed283ae89d934d5b704b697bec2f2"
+content-hash = "2233ff296b7edfbd8941172d9932f8caa41d33f484c2f4df00c63e22a16cc6ad"
 
 [metadata.files]
 aiosqlite = [
@@ -630,7 +631,8 @@ attrs = [
     {file = "attrs-20.2.0.tar.gz", hash = "sha256:26b54ddbbb9ee1d34d5d3668dd37d6cf74990ab23c828c2888dccdceee395594"},
 ]
 black = [
-    {file = "black-20.8b1.tar.gz", hash = "sha256:1c02557aa099101b9d21496f8a914e9ed2222ef70336404eeeac8edba836fbea"},
+    {file = "black-21.4b2-py3-none-any.whl", hash = "sha256:bff7067d8bc25eb21dcfdbc8c72f2baafd9ec6de4663241a52fb904b304d391f"},
+    {file = "black-21.4b2.tar.gz", hash = "sha256:fc9bcf3b482b05c1f35f6a882c079dc01b9c7795827532f4cc43c0ec88067bbc"},
 ]
 certifi = [
     {file = "certifi-2020.6.20-py2.py3-none-any.whl", hash = "sha256:8fc0819f1f30ba15bdb34cceffb9ef04d99f420f68eb75d901e9560b8749fc41"},
@@ -747,8 +749,8 @@ packaging = [
     {file = "packaging-20.4.tar.gz", hash = "sha256:4357f74f47b9c12db93624a82154e9b120fa8293699949152b22065d556079f8"},
 ]
 pathspec = [
-    {file = "pathspec-0.8.0-py2.py3-none-any.whl", hash = "sha256:7d91249d21749788d07a2d0f94147accd8f845507400749ea19c1ec9054a12b0"},
-    {file = "pathspec-0.8.0.tar.gz", hash = "sha256:da45173eb3a6f2a5a487efba21f050af2b41948be6ab52b6a1e3ff22bb8b7061"},
+    {file = "pathspec-0.8.1-py2.py3-none-any.whl", hash = "sha256:aa0cb481c4041bf52ffa7b0d8fa6cd3e88a2ca4879c533c9153882ee2556790d"},
+    {file = "pathspec-0.8.1.tar.gz", hash = "sha256:86379d6b86d75816baba717e64b1a3a3469deb93bb76d613c9ce79edc5cb68fd"},
 ]
 pluggy = [
     {file = "pluggy-0.13.1-py2.py3-none-any.whl", hash = "sha256:966c145cd83c96502c3c3868f50408687b38434af77734af1e9ca461a4081d2d"},
@@ -920,36 +922,36 @@ toml = [
     {file = "toml-0.10.1.tar.gz", hash = "sha256:926b612be1e5ce0634a2ca03470f95169cf16f939018233a670519cb4ac58b0f"},
 ]
 typed-ast = [
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-    {file = "typed_ast-1.4.1-cp36-cp36m-manylinux1_i686.whl", hash = "sha256:24995c843eb0ad11a4527b026b4dde3da70e1f2d8806c99b7b4a7cf491612652"},
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-    {file = "typed_ast-1.4.1-cp37-cp37m-macosx_10_9_x86_64.whl", hash = "sha256:8ce678dbaf790dbdb3eba24056d5364fb45944f33553dd5869b7580cdbb83614"},
-    {file = "typed_ast-1.4.1-cp37-cp37m-manylinux1_i686.whl", hash = "sha256:c9e348e02e4d2b4a8b2eedb48210430658df6951fa484e59de33ff773fbd4b41"},
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-    {file = "typed_ast-1.4.1-cp37-cp37m-win_amd64.whl", hash = "sha256:0666aa36131496aed8f7be0410ff974562ab7eeac11ef351def9ea6fa28f6355"},
-    {file = "typed_ast-1.4.1-cp38-cp38-macosx_10_15_x86_64.whl", hash = "sha256:d205b1b46085271b4e15f670058ce182bd1199e56b317bf2ec004b6a44f911f6"},
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-    {file = "typed_ast-1.4.1.tar.gz", hash = "sha256:8c8aaad94455178e3187ab22c8b01a3837f8ee50e09cf31f1ba129eb293ec30b"},
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+    {file = "typed_ast-1.4.3-cp35-cp35m-win_amd64.whl", hash = "sha256:777a26c84bea6cd934422ac2e3b78863a37017618b6e5c08f92ef69853e765d3"},
+    {file = "typed_ast-1.4.3-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:f8afcf15cc511ada719a88e013cec87c11aff7b91f019295eb4530f96fe5ef2f"},
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+    {file = "typed_ast-1.4.3-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:f328adcfebed9f11301eaedfa48e15bdece9b519fb27e6a8c01aa52a17ec31b3"},
+    {file = "typed_ast-1.4.3-cp39-cp39-manylinux1_i686.whl", hash = "sha256:2c726c276d09fc5c414693a2de063f521052d9ea7c240ce553316f70656c84d4"},
+    {file = "typed_ast-1.4.3-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:cae53c389825d3b46fb37538441f75d6aecc4174f615d048321b716df2757fb0"},
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+    {file = "typed_ast-1.4.3-cp39-cp39-win32.whl", hash = "sha256:209596a4ec71d990d71d5e0d312ac935d86930e6eecff6ccc7007fe54d703808"},
+    {file = "typed_ast-1.4.3-cp39-cp39-win_amd64.whl", hash = "sha256:9c6d1a54552b5330bc657b7ef0eae25d00ba7ffe85d9ea8ae6540d2197a3788c"},
+    {file = "typed_ast-1.4.3.tar.gz", hash = "sha256:fb1bbeac803adea29cedd70781399c99138358c26d05fcbd23c13016b7f5ec65"},
 ]
 typing-extensions = [
     {file = "typing_extensions-3.7.4.3-py2-none-any.whl", hash = "sha256:dafc7639cde7f1b6e1acc0f457842a83e722ccca8eef5270af2d74792619a89f"},
diff --git a/pyproject.toml b/pyproject.toml
index 0149145..d52453e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -31,7 +31,7 @@ aiosqlite = { version = "^0.17.0", optional = true }
 
 [tool.poetry.dev-dependencies]
 flake8 = "^3.9.0"
-black = "^20.8b1"
+black = "^21.4b2"
 pydocstyle = "^6.0.0"
 docutils = "^0.16"
 pytest = "^6.2.2"