diff --git a/bot.py b/bot.py
index 08e5268..40a0d95 100644
--- a/bot.py
+++ b/bot.py
@@ -27,11 +27,11 @@ class State:
 
 def process_event(event, template):
     if event.begin.hour == event.begin.minute == 0:
-        date_fmt = 'dddd, D. MMMM YYYY'
+        date_fmt = "dddd, D. MMMM YYYY"
     else:
-        date_fmt = 'HH:mm / dddd, D. MMMM YYYY'
+        date_fmt = "HH:mm / dddd, D. MMMM YYYY"
 
-    date = event.begin.format(date_fmt, locale='cs_CZ')
+    date = event.begin.format(date_fmt, locale="cs_CZ")
     when = event.begin.humanize()
 
     location = f"@ {event.location}" if event.location else ""
@@ -57,10 +57,10 @@ def process_event(event, template):
         location=location,
         when=when,
         url=url,
-        description=description
+        description=description,
     )
 
-    output = re.sub(r'(<br>)+', '<br>', output)
+    output = re.sub(r"(<br>)+", "<br>", output)
 
     return output
 
@@ -69,21 +69,27 @@ async def send_message(text):
     if config.WEBHOOK_URL:
         logging.debug(f"Posting via WEBHOOK.")
         async with aiohttp.ClientSession() as session:
-            result = await session.post(config.WEBHOOK_URL, json={
-                "text": text,
-                "format": "html",
-                "displayName": "PUBLIC INFORMATION STREAMS & SERVICES",
-                "avatarUrl": config.AVATAR_URL
-            })
+            result = await session.post(
+                config.WEBHOOK_URL,
+                json={
+                    "text": text,
+                    "format": "html",
+                    "displayName": "PUBLIC INFORMATION STREAMS & SERVICES",
+                    "avatarUrl": config.AVATAR_URL,
+                },
+            )
             logging.debug(f"RECV: [{result.status}] {await result.text()}")
     if config.TG_CHAT_ID and config.TG_API_KEY:
         logging.debug(f"Posting via TELEGRAM.")
         async with aiohttp.ClientSession() as session:
-            result = await session.post(f"https://api.telegram.org/bot{config.TG_API_KEY}/sendMessage", json={
-                "chat_id": config.TG_CHAT_ID,
-                "text": text.replace('<br>', '\n'),
-                "parse_mode": "html"
-            })
+            result = await session.post(
+                f"https://api.telegram.org/bot{config.TG_API_KEY}/sendMessage",
+                json={
+                    "chat_id": config.TG_CHAT_ID,
+                    "text": text.replace("<br>", "\n"),
+                    "parse_mode": "html",
+                },
+            )
             logging.debug(f"RECV: [{result.status}] {await result.text()}")
 
 
@@ -93,7 +99,7 @@ def get_event_id(event: Event) -> str:
 
 async def main():
     try:
-        with open(STATE_PATH, 'rb') as state_fp:
+        with open(STATE_PATH, "rb") as state_fp:
             state = pickle.load(state_fp)
     except FileNotFoundError:
         state = State()
@@ -106,32 +112,49 @@ async def main():
                 async with session.get(url) as resp:
                     calendars.append(Calendar(await resp.text()))
 
-        future_events = [event for calendar in calendars for event in calendar.events if event.begin > arrow.now()]
+        future_events = [
+            event
+            for calendar in calendars
+            for event in calendar.events
+            if event.begin > arrow.now()
+        ]
         logging.debug(f"Got {len(future_events)} future events...")
 
         for event in future_events:
-            if get_event_id(event) not in state.notified and event.begin.shift(days=-2) < arrow.now():
+            if (
+                get_event_id(event) not in state.notified
+                and event.begin.shift(days=-2) < arrow.now()
+            ):
                 logging.info(f"Sending description of {event.name}")
                 await send_message(process_event(event, config.EVENT_TEMPLATE))
                 state.notified.append(get_event_id(event))
 
-            if get_event_id(event) not in state.notified_soon and event.begin.shift(hours=-2) < arrow.now():
+            if (
+                get_event_id(event) not in state.notified_soon
+                and event.begin.shift(hours=-2) < arrow.now()
+            ):
                 logging.info(f"Notifying of {event.name}")
                 await send_message(process_event(event, config.SOON_TEMPLATE))
                 state.notified_soon.append(get_event_id(event))
 
-        with open(STATE_PATH, 'wb') as state_fp:
+        with open(STATE_PATH, "wb") as state_fp:
             pickle.dump(state, state_fp)
 
         logging.debug("Sleeping for 60s...")
         await sleep(60)
 
 
-if __name__ == '__main__':
-    logging.basicConfig(level=logging.DEBUG, format='%(asctime)s - [%(levelname)s] %(message)s')
+if __name__ == "__main__":
+    logging.basicConfig(
+        level=logging.DEBUG, format="%(asctime)s - [%(levelname)s] %(message)s"
+    )
 
-    if config.WEBHOOK_URL is None and (config.TG_API_KEY is None or config.TG_CHAT_ID is None):
-        raise RuntimeError("One of WEBHOOK_URL, TG_API_KEY & TG_CHAT_ID must be defined.")
+    if config.WEBHOOK_URL is None and (
+        config.TG_API_KEY is None or config.TG_CHAT_ID is None
+    ):
+        raise RuntimeError(
+            "One of WEBHOOK_URL, TG_API_KEY & TG_CHAT_ID must be defined."
+        )
 
     loop = asyncio.get_event_loop()
     loop.run_until_complete(main())
diff --git a/poetry.lock b/poetry.lock
index b5def79..683cb37 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -17,6 +17,14 @@ yarl = ">=1.0,<2.0"
 [package.extras]
 speedups = ["aiodns", "brotlipy", "cchardet"]
 
+[[package]]
+name = "appdirs"
+version = "1.4.4"
+description = "A small Python module for determining appropriate platform-specific dirs, e.g. a \"user data dir\"."
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "arrow"
 version = "0.14.7"
@@ -50,6 +58,29 @@ docs = ["furo", "sphinx", "zope.interface"]
 tests = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface"]
 tests_no_zope = ["coverage[toml] (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six"]
 
+[[package]]
+name = "black"
+version = "21.5b1"
+description = "The uncompromising code formatter."
+category = "dev"
+optional = false
+python-versions = ">=3.6.2"
+
+[package.dependencies]
+appdirs = "*"
+click = ">=7.1.2"
+mypy-extensions = ">=0.4.3"
+pathspec = ">=0.8.1,<1"
+regex = ">=2020.1.8"
+toml = ">=0.10.1"
+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 (>=3.6.0)", "aiohttp-cors"]
+python2 = ["typed-ast (>=1.4.2)"]
+
 [[package]]
 name = "chardet"
 version = "3.0.4"
@@ -58,6 +89,26 @@ category = "main"
 optional = false
 python-versions = "*"
 
+[[package]]
+name = "click"
+version = "8.0.1"
+description = "Composable command line interface toolkit"
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
+[package.dependencies]
+colorama = {version = "*", markers = "platform_system == \"Windows\""}
+importlib-metadata = {version = "*", markers = "python_version < \"3.8\""}
+
+[[package]]
+name = "colorama"
+version = "0.4.4"
+description = "Cross-platform colored terminal text."
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+
 [[package]]
 name = "ics"
 version = "0.7"
@@ -80,6 +131,22 @@ category = "main"
 optional = false
 python-versions = ">=3.4"
 
+[[package]]
+name = "importlib-metadata"
+version = "4.0.1"
+description = "Read metadata from Python packages"
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
+[package.dependencies]
+typing-extensions = {version = ">=3.6.4", markers = "python_version < \"3.8\""}
+zipp = ">=0.5"
+
+[package.extras]
+docs = ["sphinx", "jaraco.packaging (>=8.2)", "rst.linker (>=1.9)"]
+testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytest-cov", "pytest-enabler (>=1.0.1)", "packaging", "pep517", "pyfakefs", "flufl.flake8", "pytest-black (>=0.3.7)", "pytest-mypy", "importlib-resources (>=1.3)"]
+
 [[package]]
 name = "multidict"
 version = "5.1.0"
@@ -88,6 +155,22 @@ category = "main"
 optional = false
 python-versions = ">=3.6"
 
+[[package]]
+name = "mypy-extensions"
+version = "0.4.3"
+description = "Experimental type system extensions for programs checked with the mypy typechecker."
+category = "dev"
+optional = false
+python-versions = "*"
+
+[[package]]
+name = "pathspec"
+version = "0.8.1"
+description = "Utility library for gitignore style pattern matching of file paths."
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+
 [[package]]
 name = "python-dateutil"
 version = "2.8.1"
@@ -99,6 +182,14 @@ python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,>=2.7"
 [package.dependencies]
 six = ">=1.5"
 
+[[package]]
+name = "regex"
+version = "2021.4.4"
+description = "Alternative regular expression module, to replace re."
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "six"
 version = "1.15.0"
@@ -118,6 +209,22 @@ python-versions = "*"
 [package.extras]
 future-regex = ["regex"]
 
+[[package]]
+name = "toml"
+version = "0.10.2"
+description = "Python Library for Tom's Obvious, Minimal Language"
+category = "dev"
+optional = false
+python-versions = ">=2.6, !=3.0.*, !=3.1.*, !=3.2.*"
+
+[[package]]
+name = "typed-ast"
+version = "1.4.3"
+description = "a fork of Python 2 and 3 ast modules with type comment support"
+category = "dev"
+optional = false
+python-versions = "*"
+
 [[package]]
 name = "typing-extensions"
 version = "3.7.4.3"
@@ -139,10 +246,22 @@ idna = ">=2.0"
 multidict = ">=4.0"
 typing-extensions = {version = ">=3.7.4", markers = "python_version < \"3.8\""}
 
+[[package]]
+name = "zipp"
+version = "3.4.1"
+description = "Backport of pathlib-compatible object wrapper for zip files"
+category = "dev"
+optional = false
+python-versions = ">=3.6"
+
+[package.extras]
+docs = ["sphinx", "jaraco.packaging (>=8.2)", "rst.linker (>=1.9)"]
+testing = ["pytest (>=4.6)", "pytest-checkdocs (>=1.2.3)", "pytest-flake8", "pytest-cov", "pytest-enabler", "jaraco.itertools", "func-timeout", "pytest-black (>=0.3.7)", "pytest-mypy"]
+
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.7"
-content-hash = "17fb13f9e647d4a8a0f8d89fd67c3ebcdc6dd25513cf698301e0981c6b6b8a6c"
+content-hash = "474417810aabb1c095711d8046234a1c2815a8e8769055538645ba4f1287ee87"
 
 [metadata.files]
 aiohttp = [
@@ -184,6 +303,10 @@ aiohttp = [
     {file = "aiohttp-3.7.4-cp39-cp39-win_amd64.whl", hash = "sha256:40bd1b101b71a18a528ffce812cc14ff77d4a2a1272dfb8b11b200967489ef3e"},
     {file = "aiohttp-3.7.4.tar.gz", hash = "sha256:5d84ecc73141d0a0d61ece0742bb7ff5751b0657dab8405f899d3ceb104cc7de"},
 ]
+appdirs = [
+    {file = "appdirs-1.4.4-py2.py3-none-any.whl", hash = "sha256:a841dacd6b99318a741b166adb07e19ee71a274450e68237b4650ca1055ab128"},
+    {file = "appdirs-1.4.4.tar.gz", hash = "sha256:7d5d0167b2b1ba821647616af46a749d1c653740dd0d2415100fe26e27afdf41"},
+]
 arrow = [
     {file = "arrow-0.14.7-py2.py3-none-any.whl", hash = "sha256:4bfacea734ead51495dc47df00421ecfd4ca1f2c0fbe58b9a26eaeddedc31caf"},
     {file = "arrow-0.14.7.tar.gz", hash = "sha256:67f8be7c0cf420424bc62d8d7dc40b44e4bb2f7b515f9cc2954fb36e35797656"},
@@ -196,18 +319,35 @@ attrs = [
     {file = "attrs-20.3.0-py2.py3-none-any.whl", hash = "sha256:31b2eced602aa8423c2aea9c76a724617ed67cf9513173fd3a4f03e3a929c7e6"},
     {file = "attrs-20.3.0.tar.gz", hash = "sha256:832aa3cde19744e49938b91fea06d69ecb9e649c93ba974535d08ad92164f700"},
 ]
+black = [
+    {file = "black-21.5b1-py3-none-any.whl", hash = "sha256:8a60071a0043876a4ae96e6c69bd3a127dad2c1ca7c8083573eb82f92705d008"},
+    {file = "black-21.5b1.tar.gz", hash = "sha256:23695358dbcb3deafe7f0a3ad89feee5999a46be5fec21f4f1d108be0bcdb3b1"},
+]
 chardet = [
     {file = "chardet-3.0.4-py2.py3-none-any.whl", hash = "sha256:fc323ffcaeaed0e0a02bf4d117757b98aed530d9ed4531e3e15460124c106691"},
     {file = "chardet-3.0.4.tar.gz", hash = "sha256:84ab92ed1c4d4f16916e05906b6b75a6c0fb5db821cc65e70cbd64a3e2a5eaae"},
 ]
+click = [
+    {file = "click-8.0.1-py3-none-any.whl", hash = "sha256:fba402a4a47334742d782209a7c79bc448911afe1149d07bdabdf480b3e2f4b6"},
+    {file = "click-8.0.1.tar.gz", hash = "sha256:8c04c11192119b1ef78ea049e0a6f0463e4c48ef00a30160c704337586f3ad7a"},
+]
+colorama = [
+    {file = "colorama-0.4.4-py2.py3-none-any.whl", hash = "sha256:9f47eda37229f68eee03b24b9748937c7dc3868f906e8ba69fbcbdd3bc5dc3e2"},
+    {file = "colorama-0.4.4.tar.gz", hash = "sha256:5941b2b48a20143d2267e95b1c2a7603ce057ee39fd88e7329b0c292aa16869b"},
+]
 ics = [
     {file = "ics-0.7-py2.py3-none-any.whl", hash = "sha256:bf5fbdef6e1e073afdadf1b996f0271186dd114a148e38e795919a1ae644d6ac"},
     {file = "ics-0.7-py3.7.egg", hash = "sha256:3b606205b9582ad27dff77f9b227a30d02fdac532731927fe39df1f1ddf8673f"},
+    {file = "ics-0.7.tar.gz", hash = "sha256:81113a2bb3166c1afcd71cd450c968d40efc385601e9d8344733e00ad8f53429"},
 ]
 idna = [
     {file = "idna-3.1-py3-none-any.whl", hash = "sha256:5205d03e7bcbb919cc9c19885f9920d622ca52448306f2377daede5cf3faac16"},
     {file = "idna-3.1.tar.gz", hash = "sha256:c5b02147e01ea9920e6b0a3f1f7bb833612d507592c837a6c49552768f4054e1"},
 ]
+importlib-metadata = [
+    {file = "importlib_metadata-4.0.1-py3-none-any.whl", hash = "sha256:d7eb1dea6d6a6086f8be21784cc9e3bcfa55872b52309bc5fad53a8ea444465d"},
+    {file = "importlib_metadata-4.0.1.tar.gz", hash = "sha256:8c501196e49fb9df5df43833bdb1e4328f64847763ec8a50703148b73784d581"},
+]
 multidict = [
     {file = "multidict-5.1.0-cp36-cp36m-macosx_10_14_x86_64.whl", hash = "sha256:b7993704f1a4b204e71debe6095150d43b2ee6150fa4f44d6d966ec356a8d61f"},
     {file = "multidict-5.1.0-cp36-cp36m-manylinux1_i686.whl", hash = "sha256:9dd6e9b1a913d096ac95d0399bd737e00f2af1e1594a787e00f7975778c8b2bf"},
@@ -247,10 +387,61 @@ multidict = [
     {file = "multidict-5.1.0-cp39-cp39-win_amd64.whl", hash = "sha256:7df80d07818b385f3129180369079bd6934cf70469f99daaebfac89dca288359"},
     {file = "multidict-5.1.0.tar.gz", hash = "sha256:25b4e5f22d3a37ddf3effc0710ba692cfc792c2b9edfb9c05aefe823256e84d5"},
 ]
+mypy-extensions = [
+    {file = "mypy_extensions-0.4.3-py2.py3-none-any.whl", hash = "sha256:090fedd75945a69ae91ce1303b5824f428daf5a028d2f6ab8a299250a846f15d"},
+    {file = "mypy_extensions-0.4.3.tar.gz", hash = "sha256:2d82818f5bb3e369420cb3c4060a7970edba416647068eb4c5343488a6c604a8"},
+]
+pathspec = [
+    {file = "pathspec-0.8.1-py2.py3-none-any.whl", hash = "sha256:aa0cb481c4041bf52ffa7b0d8fa6cd3e88a2ca4879c533c9153882ee2556790d"},
+    {file = "pathspec-0.8.1.tar.gz", hash = "sha256:86379d6b86d75816baba717e64b1a3a3469deb93bb76d613c9ce79edc5cb68fd"},
+]
 python-dateutil = [
     {file = "python-dateutil-2.8.1.tar.gz", hash = "sha256:73ebfe9dbf22e832286dafa60473e4cd239f8592f699aa5adaf10050e6e1823c"},
     {file = "python_dateutil-2.8.1-py2.py3-none-any.whl", hash = "sha256:75bb3f31ea686f1197762692a9ee6a7550b59fc6ca3a1f4b5d7e32fb98e2da2a"},
 ]
+regex = [
+    {file = "regex-2021.4.4-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:619d71c59a78b84d7f18891fe914446d07edd48dc8328c8e149cbe0929b4e000"},
+    {file = "regex-2021.4.4-cp36-cp36m-manylinux1_i686.whl", hash = "sha256:47bf5bf60cf04d72bf6055ae5927a0bd9016096bf3d742fa50d9bf9f45aa0711"},
+    {file = "regex-2021.4.4-cp36-cp36m-manylinux1_x86_64.whl", hash = "sha256:281d2fd05555079448537fe108d79eb031b403dac622621c78944c235f3fcf11"},
+    {file = "regex-2021.4.4-cp36-cp36m-manylinux2010_i686.whl", hash = "sha256:bd28bc2e3a772acbb07787c6308e00d9626ff89e3bfcdebe87fa5afbfdedf968"},
+    {file = "regex-2021.4.4-cp36-cp36m-manylinux2010_x86_64.whl", hash = "sha256:7c2a1af393fcc09e898beba5dd59196edaa3116191cc7257f9224beaed3e1aa0"},
+    {file = "regex-2021.4.4-cp36-cp36m-manylinux2014_aarch64.whl", hash = "sha256:c38c71df845e2aabb7fb0b920d11a1b5ac8526005e533a8920aea97efb8ec6a4"},
+    {file = "regex-2021.4.4-cp36-cp36m-manylinux2014_i686.whl", hash = "sha256:96fcd1888ab4d03adfc9303a7b3c0bd78c5412b2bfbe76db5b56d9eae004907a"},
+    {file = "regex-2021.4.4-cp36-cp36m-manylinux2014_x86_64.whl", hash = "sha256:ade17eb5d643b7fead300a1641e9f45401c98eee23763e9ed66a43f92f20b4a7"},
+    {file = "regex-2021.4.4-cp36-cp36m-win32.whl", hash = "sha256:e8e5b509d5c2ff12f8418006d5a90e9436766133b564db0abaec92fd27fcee29"},
+    {file = "regex-2021.4.4-cp36-cp36m-win_amd64.whl", hash = "sha256:11d773d75fa650cd36f68d7ca936e3c7afaae41b863b8c387a22aaa78d3c5c79"},
+    {file = "regex-2021.4.4-cp37-cp37m-macosx_10_9_x86_64.whl", hash = "sha256:d3029c340cfbb3ac0a71798100ccc13b97dddf373a4ae56b6a72cf70dfd53bc8"},
+    {file = "regex-2021.4.4-cp37-cp37m-manylinux1_i686.whl", hash = "sha256:18c071c3eb09c30a264879f0d310d37fe5d3a3111662438889ae2eb6fc570c31"},
+    {file = "regex-2021.4.4-cp37-cp37m-manylinux1_x86_64.whl", hash = "sha256:4c557a7b470908b1712fe27fb1ef20772b78079808c87d20a90d051660b1d69a"},
+    {file = "regex-2021.4.4-cp37-cp37m-manylinux2010_i686.whl", hash = "sha256:01afaf2ec48e196ba91b37451aa353cb7eda77efe518e481707e0515025f0cd5"},
+    {file = "regex-2021.4.4-cp37-cp37m-manylinux2010_x86_64.whl", hash = "sha256:3a9cd17e6e5c7eb328517969e0cb0c3d31fd329298dd0c04af99ebf42e904f82"},
+    {file = "regex-2021.4.4-cp37-cp37m-manylinux2014_aarch64.whl", hash = "sha256:90f11ff637fe8798933fb29f5ae1148c978cccb0452005bf4c69e13db951e765"},
+    {file = "regex-2021.4.4-cp37-cp37m-manylinux2014_i686.whl", hash = "sha256:919859aa909429fb5aa9cf8807f6045592c85ef56fdd30a9a3747e513db2536e"},
+    {file = "regex-2021.4.4-cp37-cp37m-manylinux2014_x86_64.whl", hash = "sha256:339456e7d8c06dd36a22e451d58ef72cef293112b559010db3d054d5560ef439"},
+    {file = "regex-2021.4.4-cp37-cp37m-win32.whl", hash = "sha256:67bdb9702427ceddc6ef3dc382455e90f785af4c13d495f9626861763ee13f9d"},
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+    {file = "regex-2021.4.4-cp38-cp38-manylinux1_x86_64.whl", hash = "sha256:6d1b01031dedf2503631d0903cb563743f397ccaf6607a5e3b19a3d76fc10480"},
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+    {file = "regex-2021.4.4-cp38-cp38-manylinux2010_x86_64.whl", hash = "sha256:4c46e22a0933dd783467cf32b3516299fb98cfebd895817d685130cc50cd1093"},
+    {file = "regex-2021.4.4-cp38-cp38-manylinux2014_aarch64.whl", hash = "sha256:e512d8ef5ad7b898cdb2d8ee1cb09a8339e4f8be706d27eaa180c2f177248a10"},
+    {file = "regex-2021.4.4-cp38-cp38-manylinux2014_i686.whl", hash = "sha256:980d7be47c84979d9136328d882f67ec5e50008681d94ecc8afa8a65ed1f4a6f"},
+    {file = "regex-2021.4.4-cp38-cp38-manylinux2014_x86_64.whl", hash = "sha256:ce15b6d103daff8e9fee13cf7f0add05245a05d866e73926c358e871221eae87"},
+    {file = "regex-2021.4.4-cp38-cp38-win32.whl", hash = "sha256:a91aa8619b23b79bcbeb37abe286f2f408d2f2d6f29a17237afda55bb54e7aac"},
+    {file = "regex-2021.4.4-cp38-cp38-win_amd64.whl", hash = "sha256:c0502c0fadef0d23b128605d69b58edb2c681c25d44574fc673b0e52dce71ee2"},
+    {file = "regex-2021.4.4-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:598585c9f0af8374c28edd609eb291b5726d7cbce16be6a8b95aa074d252ee17"},
+    {file = "regex-2021.4.4-cp39-cp39-manylinux1_i686.whl", hash = "sha256:ee54ff27bf0afaf4c3b3a62bcd016c12c3fdb4ec4f413391a90bd38bc3624605"},
+    {file = "regex-2021.4.4-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:7d9884d86dd4dd489e981d94a65cd30d6f07203d90e98f6f657f05170f6324c9"},
+    {file = "regex-2021.4.4-cp39-cp39-manylinux2010_i686.whl", hash = "sha256:bf5824bfac591ddb2c1f0a5f4ab72da28994548c708d2191e3b87dd207eb3ad7"},
+    {file = "regex-2021.4.4-cp39-cp39-manylinux2010_x86_64.whl", hash = "sha256:563085e55b0d4fb8f746f6a335893bda5c2cef43b2f0258fe1020ab1dd874df8"},
+    {file = "regex-2021.4.4-cp39-cp39-manylinux2014_aarch64.whl", hash = "sha256:b9c3db21af35e3b3c05764461b262d6f05bbca08a71a7849fd79d47ba7bc33ed"},
+    {file = "regex-2021.4.4-cp39-cp39-manylinux2014_i686.whl", hash = "sha256:3916d08be28a1149fb97f7728fca1f7c15d309a9f9682d89d79db75d5e52091c"},
+    {file = "regex-2021.4.4-cp39-cp39-manylinux2014_x86_64.whl", hash = "sha256:fd45ff9293d9274c5008a2054ecef86a9bfe819a67c7be1afb65e69b405b3042"},
+    {file = "regex-2021.4.4-cp39-cp39-win32.whl", hash = "sha256:fa4537fb4a98fe8fde99626e4681cc644bdcf2a795038533f9f711513a862ae6"},
+    {file = "regex-2021.4.4-cp39-cp39-win_amd64.whl", hash = "sha256:97f29f57d5b84e73fbaf99ab3e26134e6687348e95ef6b48cfd2c06807005a07"},
+    {file = "regex-2021.4.4.tar.gz", hash = "sha256:52ba3d3f9b942c49d7e4bc105bb28551c44065f139a65062ab7912bef10c9afb"},
+]
 six = [
     {file = "six-1.15.0-py2.py3-none-any.whl", hash = "sha256:8b74bedcbbbaca38ff6d7491d76f2b06b3592611af620f8426e82dddb04a5ced"},
     {file = "six-1.15.0.tar.gz", hash = "sha256:30639c035cdb23534cd4aa2dd52c3bf48f06e5f4a941509c8bafd8ce11080259"},
@@ -259,6 +450,42 @@ tatsu = [
     {file = "TatSu-4.4.0-py2.py3-none-any.whl", hash = "sha256:c9211eeee9a2d4c90f69879ec0b518b1aa0d9450249cb0dd181f5f5b18be0a92"},
     {file = "TatSu-4.4.0.zip", hash = "sha256:80713413473a009f2081148d0f494884cabaf9d6866b71f2a68a92b6442f343d"},
 ]
+toml = [
+    {file = "toml-0.10.2-py2.py3-none-any.whl", hash = "sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b"},
+    {file = "toml-0.10.2.tar.gz", hash = "sha256:b3bda1d108d5dd99f4a20d24d9c348e91c4db7ab1b749200bded2f839ccbe68f"},
+]
+typed-ast = [
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+    {file = "typed_ast-1.4.3-cp35-cp35m-manylinux1_x86_64.whl", hash = "sha256:c907f561b1e83e93fad565bac5ba9c22d96a54e7ea0267c708bffe863cbe4075"},
+    {file = "typed_ast-1.4.3-cp35-cp35m-manylinux2014_aarch64.whl", hash = "sha256:1b3ead4a96c9101bef08f9f7d1217c096f31667617b58de957f690c92378b528"},
+    {file = "typed_ast-1.4.3-cp35-cp35m-win32.whl", hash = "sha256:dde816ca9dac1d9c01dd504ea5967821606f02e510438120091b84e852367428"},
+    {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-cp37-cp37m-macosx_10_9_x86_64.whl", hash = "sha256:0fb71b8c643187d7492c1f8352f2c15b4c4af3f6338f21681d3681b3dc31a266"},
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+    {file = "typed_ast-1.4.3-cp37-cp37m-manylinux1_x86_64.whl", hash = "sha256:5feca99c17af94057417d744607b82dd0a664fd5e4ca98061480fd8b14b18d04"},
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+    {file = "typed_ast-1.4.3-cp37-cp37m-win32.whl", hash = "sha256:aee0c1256be6c07bd3e1263ff920c325b59849dc95392a05f258bb9b259cf39c"},
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+    {file = "typed_ast-1.4.3-cp38-cp38-manylinux1_x86_64.whl", hash = "sha256:7538e495704e2ccda9b234b82423a4038f324f3a10c43bc088a1636180f11a41"},
+    {file = "typed_ast-1.4.3-cp38-cp38-manylinux2014_aarch64.whl", hash = "sha256:af3d4a73793725138d6b334d9d247ce7e5f084d96284ed23f22ee626a7b88e39"},
+    {file = "typed_ast-1.4.3-cp38-cp38-win32.whl", hash = "sha256:f2362f3cb0f3172c42938946dbc5b7843c2a28aec307c49100c8b38764eb6927"},
+    {file = "typed_ast-1.4.3-cp38-cp38-win_amd64.whl", hash = "sha256:dd4a21253f42b8d2b48410cb31fe501d32f8b9fbeb1f55063ad102fe9c425e40"},
+    {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"},
+    {file = "typed_ast-1.4.3-cp39-cp39-manylinux2014_aarch64.whl", hash = "sha256:b9574c6f03f685070d859e75c7f9eeca02d6933273b5e69572e5ff9d5e3931c3"},
+    {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"},
     {file = "typing_extensions-3.7.4.3-py3-none-any.whl", hash = "sha256:7cb407020f00f7bfc3cb3e7881628838e69d8f3fcab2f64742a5e76b2f841918"},
@@ -303,3 +530,7 @@ yarl = [
     {file = "yarl-1.6.3-cp39-cp39-win_amd64.whl", hash = "sha256:4953fb0b4fdb7e08b2f3b3be80a00d28c5c8a2056bb066169de00e6501b986b6"},
     {file = "yarl-1.6.3.tar.gz", hash = "sha256:8a9066529240171b68893d60dca86a763eae2139dd42f42106b03cf4b426bf10"},
 ]
+zipp = [
+    {file = "zipp-3.4.1-py3-none-any.whl", hash = "sha256:51cb66cc54621609dd593d1787f286ee42a5c0adbb4b29abea5a63edc3e03098"},
+    {file = "zipp-3.4.1.tar.gz", hash = "sha256:3607921face881ba3e026887d8150cca609d517579abe052ac81fc5aeffdbd76"},
+]
diff --git a/pyproject.toml b/pyproject.toml
index 3ad934a..c899069 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -11,6 +11,7 @@ aiohttp = "^3.7.4"
 ics = "^0.7"
 
 [tool.poetry.dev-dependencies]
+black = {version = "^21.5b1", allow-prereleases = true}
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]