diff --git a/.github/workflows/black.yml b/.github/workflows/black.yml
index 2ddee4a..cce9526 100644
--- a/.github/workflows/black.yml
+++ b/.github/workflows/black.yml
@@ -2,9 +2,9 @@ name: Code style
 
 on:
   push:
-    branches: [main, features]
+    branches: [master, features]
   pull_request:
-    branches: [main, features]
+    branches: [master, features]
 
 jobs:
   lint:
@@ -16,4 +16,5 @@ jobs:
     - uses: actions/setup-python@v2
       with:
         python-version: 3.9
-    - uses: psf/black@20.8b1
+    - uses: psf/black@21.7b0
+
diff --git a/Pipfile.lock b/Pipfile.lock
index 2d4b0da..10bdd56 100644
--- a/Pipfile.lock
+++ b/Pipfile.lock
@@ -39,37 +39,37 @@
         },
         "numpy": {
             "hashes": [
-                "sha256:1a784e8ff7ea2a32e393cc53eb0003eca1597c7ca628227e34ce34eb11645a0e",
-                "sha256:2ba579dde0563f47021dcd652253103d6fd66165b18011dce1a0609215b2791e",
-                "sha256:3537b967b350ad17633b35c2f4b1a1bbd258c018910b518c30b48c8e41272717",
-                "sha256:3c40e6b860220ed862e8097b8f81c9af6d7405b723f4a7af24a267b46f90e461",
-                "sha256:598fe100b2948465cf3ed64b1a326424b5e4be2670552066e17dfaa67246011d",
-                "sha256:620732f42259eb2c4642761bd324462a01cdd13dd111740ce3d344992dd8492f",
-                "sha256:709884863def34d72b183d074d8ba5cfe042bc3ff8898f1ffad0209161caaa99",
-                "sha256:75579acbadbf74e3afd1153da6177f846212ea2a0cc77de53523ae02c9256513",
-                "sha256:7c55407f739f0bfcec67d0df49103f9333edc870061358ac8a8c9e37ea02fcd2",
-                "sha256:a1f2fb2da242568af0271455b89aee0f71e4e032086ee2b4c5098945d0e11cf6",
-                "sha256:a290989cd671cd0605e9c91a70e6df660f73ae87484218e8285c6522d29f6e38",
-                "sha256:ac4fd578322842dbda8d968e3962e9f22e862b6ec6e3378e7415625915e2da4d",
-                "sha256:ad09f55cc95ed8d80d8ab2052f78cc21cb231764de73e229140d81ff49d8145e",
-                "sha256:b9205711e5440954f861ceeea8f1b415d7dd15214add2e878b4d1cf2bcb1a914",
-                "sha256:bba474a87496d96e61461f7306fba2ebba127bed7836212c360f144d1e72ac54",
-                "sha256:bebab3eaf0641bba26039fb0b2c5bf9b99407924b53b1ea86e03c32c64ef5aef",
-                "sha256:cc367c86eb87e5b7c9592935620f22d13b090c609f1b27e49600cd033b529f54",
-                "sha256:ccc6c650f8700ce1e3a77668bb7c43e45c20ac06ae00d22bdf6760b38958c883",
-                "sha256:cf680682ad0a3bef56dae200dbcbac2d57294a73e5b0f9864955e7dd7c2c2491",
-                "sha256:d2910d0a075caed95de1a605df00ee03b599de5419d0b95d55342e9a33ad1fb3",
-                "sha256:d5caa946a9f55511e76446e170bdad1d12d6b54e17a2afe7b189112ed4412bb8",
-                "sha256:d89b0dc7f005090e32bb4f9bf796e1dcca6b52243caf1803fdd2b748d8561f63",
-                "sha256:d95d16204cd51ff1a1c8d5f9958ce90ae190be81d348b514f9be39f878b8044a",
-                "sha256:e4d5a86a5257843a18fb1220c5f1c199532bc5d24e849ed4b0289fb59fbd4d8f",
-                "sha256:e58ddb53a7b4959932f5582ac455ff90dcb05fac3f8dcc8079498d43afbbde6c",
-                "sha256:e80fe25cba41c124d04c662f33f6364909b985f2eb5998aaa5ae4b9587242cce",
-                "sha256:eda2829af498946c59d8585a9fd74da3f810866e05f8df03a86f70079c7531dd",
-                "sha256:fd0a359c1c17f00cb37de2969984a74320970e0ceef4808c32e00773b06649d9"
+                "sha256:01721eefe70544d548425a07c80be8377096a54118070b8a62476866d5208e33",
+                "sha256:0318c465786c1f63ac05d7c4dbcecd4d2d7e13f0959b01b534ea1e92202235c5",
+                "sha256:05a0f648eb28bae4bcb204e6fd14603de2908de982e761a2fc78efe0f19e96e1",
+                "sha256:1412aa0aec3e00bc23fbb8664d76552b4efde98fb71f60737c83efbac24112f1",
+                "sha256:25b40b98ebdd272bc3020935427a4530b7d60dfbe1ab9381a39147834e985eac",
+                "sha256:2d4d1de6e6fb3d28781c73fbde702ac97f03d79e4ffd6598b880b2d95d62ead4",
+                "sha256:38e8648f9449a549a7dfe8d8755a5979b45b3538520d1e735637ef28e8c2dc50",
+                "sha256:4a3d5fb89bfe21be2ef47c0614b9c9c707b7362386c9a3ff1feae63e0267ccb6",
+                "sha256:635e6bd31c9fb3d475c8f44a089569070d10a9ef18ed13738b03049280281267",
+                "sha256:73101b2a1fef16602696d133db402a7e7586654682244344b8329cdcbbb82172",
+                "sha256:791492091744b0fe390a6ce85cc1bf5149968ac7d5f0477288f78c89b385d9af",
+                "sha256:7a708a79c9a9d26904d1cca8d383bf869edf6f8e7650d85dbc77b041e8c5a0f8",
+                "sha256:88c0b89ad1cc24a5efbb99ff9ab5db0f9a86e9cc50240177a571fbe9c2860ac2",
+                "sha256:8a326af80e86d0e9ce92bcc1e65c8ff88297de4fa14ee936cb2293d414c9ec63",
+                "sha256:8a92c5aea763d14ba9d6475803fc7904bda7decc2a0a68153f587ad82941fec1",
+                "sha256:91c6f5fc58df1e0a3cc0c3a717bb3308ff850abdaa6d2d802573ee2b11f674a8",
+                "sha256:95b995d0c413f5d0428b3f880e8fe1660ff9396dcd1f9eedbc311f37b5652e16",
+                "sha256:9749a40a5b22333467f02fe11edc98f022133ee1bfa8ab99bda5e5437b831214",
+                "sha256:978010b68e17150db8765355d1ccdd450f9fc916824e8c4e35ee620590e234cd",
+                "sha256:9a513bd9c1551894ee3d31369f9b07460ef223694098cf27d399513415855b68",
+                "sha256:a75b4498b1e93d8b700282dc8e655b8bd559c0904b3910b144646dbbbc03e062",
+                "sha256:c6a2324085dd52f96498419ba95b5777e40b6bcbc20088fddb9e8cbb58885e8e",
+                "sha256:d7a4aeac3b94af92a9373d6e77b37691b86411f9745190d2c351f410ab3a791f",
+                "sha256:d9e7912a56108aba9b31df688a4c4f5cb0d9d3787386b87d504762b6754fbb1b",
+                "sha256:dff4af63638afcc57a3dfb9e4b26d434a7a602d225b42d746ea7fe2edf1342fd",
+                "sha256:e46ceaff65609b5399163de5893d8f2a82d3c77d5e56d976c8b5fb01faa6b671",
+                "sha256:f01f28075a92eede918b965e86e8f0ba7b7797a95aa8d35e1cc8821f5fc3ad6a",
+                "sha256:fd7d7409fa643a91d0a05c7554dd68aa9c9bb16e186f6ccfe40d6e003156e33a"
             ],
             "markers": "python_version >= '3.7'",
-            "version": "==1.21.0"
+            "version": "==1.21.1"
         },
         "python-dateutil": {
             "hashes": [
@@ -161,11 +161,11 @@
         },
         "black": {
             "hashes": [
-                "sha256:dc132348a88d103016726fe360cb9ede02cecf99b76e3660ce6c596be132ce04",
-                "sha256:dfb8c5a069012b2ab1e972e7b908f5fb42b6bbabcba0a788b86dc05067c7d9c7"
+                "sha256:1c7aa6ada8ee864db745b22790a32f94b2795c253a75d6d9b5e439ff10d23116",
+                "sha256:c8373c6491de9362e39271630b65b964607bc5c79c83783547d76c839b3aa219"
             ],
             "index": "pypi",
-            "version": "==21.6b0"
+            "version": "==21.7b0"
         },
         "click": {
             "hashes": [
@@ -184,10 +184,10 @@
         },
         "pathspec": {
             "hashes": [
-                "sha256:86379d6b86d75816baba717e64b1a3a3469deb93bb76d613c9ce79edc5cb68fd",
-                "sha256:aa0cb481c4041bf52ffa7b0d8fa6cd3e88a2ca4879c533c9153882ee2556790d"
+                "sha256:7d15c4ddb0b5c802d161efc417ec1a2558ea2653c2e8ad9c19098201dc1c993a",
+                "sha256:e564499435a2673d586f6b2130bb5b95f04a3ba06f81b8f895b651a3c76aabb1"
             ],
-            "version": "==0.8.1"
+            "version": "==0.9.0"
         },
         "pytz": {
             "hashes": [
@@ -242,13 +242,13 @@
             ],
             "version": "==2021.7.6"
         },
-        "toml": {
+        "tomli": {
             "hashes": [
-                "sha256:806143ae5bfb6a3c6e736a764057db0e6a0e05e338b5630894a5f779cabb4f9b",
-                "sha256:b3bda1d108d5dd99f4a20d24d9c348e91c4db7ab1b749200bded2f839ccbe68f"
+                "sha256:0713b16ff91df8638a6a694e295c8159ab35ba93e3424a626dd5226d386057be",
+                "sha256:be670d0d8d7570fd0ea0113bd7bb1ba3ac6706b4de062cc4c952769355c9c268"
             ],
-            "markers": "python_version >= '2.6' and python_version not in '3.0, 3.1, 3.2, 3.3'",
-            "version": "==0.10.2"
+            "markers": "python_version >= '3.6'",
+            "version": "==1.0.4"
         }
     }
 }
diff --git a/_kosmorro/__version__.py b/_kosmorro/__version__.py
index 8ef13af..e63786f 100644
--- a/_kosmorro/__version__.py
+++ b/_kosmorro/__version__.py
@@ -19,7 +19,7 @@
 __title__ = "kosmorro"
 __description__ = "A program that computes your ephemerides"
 __url__ = "https://kosmorro.space"
-__version__ = '0.10.1'
+__version__ = "0.10.1"
 __author__ = "Jérôme Deuchnord"
 __author_email__ = "jerome@deuchnord.fr"
 __license__ = "AGPL"
diff --git a/_kosmorro/debug.py b/_kosmorro/debug.py
index f1b18f0..6c9fe39 100644
--- a/_kosmorro/debug.py
+++ b/_kosmorro/debug.py
@@ -13,4 +13,3 @@ def debug_print(what, force: bool = False):
         print_exception(type(what), value=what, tb=None)
     else:
         print("[DEBUG] %s" % what)
-
diff --git a/_kosmorro/dumper.py b/_kosmorro/dumper.py
index 24f38b7..3cec6e7 100644
--- a/_kosmorro/dumper.py
+++ b/_kosmorro/dumper.py
@@ -447,8 +447,7 @@ class _LatexDumper(Dumper):
                 continue
 
             latex.append(
-                r"\event{%s}{%s}"
-                % (event.start_time.strftime(TIME_FORMAT), event_name)
+                r"\event{%s}{%s}" % (event.start_time.strftime(TIME_FORMAT), event_name)
             )
 
         return "".join(latex)
diff --git a/_kosmorro/i18n/strings.py b/_kosmorro/i18n/strings.py
index 28eea01..f52067e 100644
--- a/_kosmorro/i18n/strings.py
+++ b/_kosmorro/i18n/strings.py
@@ -10,7 +10,14 @@ def from_event(event: Event, with_description: bool = True) -> str:
         EventType.OPPOSITION: (_("%s is in opposition"), None),
         EventType.CONJUNCTION: (_("%s and %s are in conjunction"), None),
         EventType.OCCULTATION: (_("%s occults %s"), None),
-        EventType.MAXIMAL_ELONGATION: (_("Elongation of %s is maximal"),  ('{:.3n}°'.format(event.details['deg']) if type(event.details) is dict else event.details)),
+        EventType.MAXIMAL_ELONGATION: (
+            _("Elongation of %s is maximal"),
+            (
+                "{:.3n}°".format(event.details["deg"])
+                if type(event.details) is dict
+                else event.details
+            ),
+        ),
         EventType.MOON_PERIGEE: (_("%s is at its perigee"), None),
         EventType.MOON_APOGEE: (_("%s is at its apogee"), None),
     }.get(event.event_type)
@@ -21,7 +28,7 @@ def from_event(event: Event, with_description: bool = True) -> str:
     string = string % tuple([from_object(o.identifier) for o in event.objects])
 
     if details is not None and with_description:
-        return '%s (%s)' % (string, details)
+        return "%s (%s)" % (string, details)
 
     return string
 
diff --git a/_kosmorro/locales/messages.pot b/_kosmorro/locales/messages.pot
index e1260f7..e244f43 100644
--- a/_kosmorro/locales/messages.pot
+++ b/_kosmorro/locales/messages.pot
@@ -8,7 +8,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: kosmorro 0.10.1\n"
 "Report-Msgid-Bugs-To: EMAIL@ADDRESS\n"
-"POT-Creation-Date: 2021-06-20 16:08+0200\n"
+"POT-Creation-Date: 2021-07-19 12:19+0200\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -96,7 +96,7 @@ msgstr ""
 msgid "Expected events"
 msgstr ""
 
-#: _kosmorro/dumper.py:492
+#: _kosmorro/dumper.py:491
 msgid ""
 "Building PDF was not possible, because some dependencies are not "
 "installed.\n"
@@ -104,7 +104,7 @@ msgid ""
 "pdf/ for more information."
 msgstr ""
 
-#: _kosmorro/dumper.py:545
+#: _kosmorro/dumper.py:544
 #, python-format
 msgid ""
 "An error occurred during the compilation of the PDF.\n"
@@ -238,90 +238,90 @@ msgstr ""
 msgid "%s occults %s"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:13
+#: _kosmorro/i18n/strings.py:14
 #, python-format
 msgid "Elongation of %s is maximal"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:14
+#: _kosmorro/i18n/strings.py:21
 #, python-format
 msgid "%s is at its perigee"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:15
+#: _kosmorro/i18n/strings.py:22
 #, python-format
 msgid "%s is at its apogee"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:31
+#: _kosmorro/i18n/strings.py:38
 msgid "New Moon"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:32
+#: _kosmorro/i18n/strings.py:39
 msgid "Waxing Crescent"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:33
+#: _kosmorro/i18n/strings.py:40
 msgid "First Quarter"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:34
+#: _kosmorro/i18n/strings.py:41
 msgid "Waxing Gibbous"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:35
+#: _kosmorro/i18n/strings.py:42
 msgid "Full Moon"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:36
+#: _kosmorro/i18n/strings.py:43
 msgid "Waning Gibbous"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:37
+#: _kosmorro/i18n/strings.py:44
 msgid "Last Quarter"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:38
+#: _kosmorro/i18n/strings.py:45
 msgid "Waning Crescent"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:49
+#: _kosmorro/i18n/strings.py:56
 msgid "Sun"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:50
+#: _kosmorro/i18n/strings.py:57
 msgid "Moon"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:51
+#: _kosmorro/i18n/strings.py:58
 msgid "Mercury"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:52
+#: _kosmorro/i18n/strings.py:59
 msgid "Venus"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:53
+#: _kosmorro/i18n/strings.py:60
 msgid "Mars"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:54
+#: _kosmorro/i18n/strings.py:61
 msgid "Jupiter"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:55
+#: _kosmorro/i18n/strings.py:62
 msgid "Saturn"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:56
+#: _kosmorro/i18n/strings.py:63
 msgid "Uranus"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:57
+#: _kosmorro/i18n/strings.py:64
 msgid "Neptune"
 msgstr ""
 
-#: _kosmorro/i18n/strings.py:58
+#: _kosmorro/i18n/strings.py:65
 msgid "Pluto"
 msgstr ""