We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
testing #2252 follow mail: mail participation ends soon
Where: Mail "participation ends soon"

* in a single module project link should go to project view and not to a module view that does not regularly exist in this case. Is that possible?
* As in the other mails: paragraph between two sentences probably looks better.

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `meinberlin/apps/offlineevents/models.py`
Content:
```
1 from datetime import timedelta
2 
3 from autoslug import AutoSlugField
4 from ckeditor_uploader.fields import RichTextUploadingField
5 from django.db import models
6 from django.urls import reverse
7 from django.utils import timezone
8 from django.utils.translation import ugettext_lazy as _
9 
10 from adhocracy4 import transforms
11 from adhocracy4.models.base import UserGeneratedContentModel
12 from adhocracy4.projects import models as project_models
13 
14 
15 class OfflineEventsQuerySet(models.QuerySet):
16 
17     def starts_within(self, hours=72):
18         """All offlineevents starting within the given time."""
19         now = timezone.now()
20         return self.filter(date__gt=now,
21                            date__lt=(now + timedelta(hours=hours)))
22 
23 
24 class OfflineEvent(UserGeneratedContentModel):
25     slug = AutoSlugField(populate_from='name', unique=True)
26     name = models.CharField(max_length=120, verbose_name=_('Name of event'))
27     event_type = models.CharField(
28         max_length=30, verbose_name=_('Event type'),
29         help_text=_('The content of this field is shown in the timeline. It '
30                     'should have no more than 30 characters e.g. Information '
31                     'event or 3rd public workshop.'))
32     date = models.DateTimeField(
33         verbose_name=_('Date'))
34     description = RichTextUploadingField(
35         config_name='image-editor',
36         verbose_name=_('Description'))
37     project = models.ForeignKey(
38         project_models.Project, on_delete=models.CASCADE)
39 
40     objects = OfflineEventsQuerySet.as_manager()
41 
42     class Meta:
43         ordering = ['-date']
44 
45     def __str__(self):
46         return self.name
47 
48     def save(self, *args, **kwargs):
49         self.description = transforms.clean_html_field(
50             self.description, 'image-editor')
51         super().save(*args, **kwargs)
52 
53     def get_absolute_url(self):
54         return reverse('meinberlin_offlineevents:offlineevent-detail',
55                        args=[str(self.slug)])
56
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/meinberlin/apps/offlineevents/models.py b/meinberlin/apps/offlineevents/models.py
--- a/meinberlin/apps/offlineevents/models.py
+++ b/meinberlin/apps/offlineevents/models.py
@@ -3,8 +3,8 @@
 from autoslug import AutoSlugField
 from ckeditor_uploader.fields import RichTextUploadingField
 from django.db import models
-from django.urls import reverse
 from django.utils import timezone
+from django.utils.functional import cached_property
 from django.utils.translation import ugettext_lazy as _
 
 from adhocracy4 import transforms
@@ -50,6 +50,16 @@
             self.description, 'image-editor')
         super().save(*args, **kwargs)
 
+    @cached_property
+    def get_timeline_index(self):
+        if self.project.display_timeline:
+            for count, cluster in enumerate(self.project.participation_dates):
+                if 'event_type' in cluster and self.slug == cluster['slug']:
+                    return count
+        return 0
+
     def get_absolute_url(self):
-        return reverse('meinberlin_offlineevents:offlineevent-detail',
-                       args=[str(self.slug)])
+        if self.project.display_timeline:
+            return '{}?initialSlide={}'.format(self.project.get_absolute_url(),
+                                               self.get_timeline_index)
+        return self.project.get_absolute_url()

{"golden_diff": "diff --git a/meinberlin/apps/offlineevents/models.py b/meinberlin/apps/offlineevents/models.py\n--- a/meinberlin/apps/offlineevents/models.py\n+++ b/meinberlin/apps/offlineevents/models.py\n@@ -3,8 +3,8 @@\n from autoslug import AutoSlugField\n from ckeditor_uploader.fields import RichTextUploadingField\n from django.db import models\n-from django.urls import reverse\n from django.utils import timezone\n+from django.utils.functional import cached_property\n from django.utils.translation import ugettext_lazy as _\n \n from adhocracy4 import transforms\n@@ -50,6 +50,16 @@\n             self.description, 'image-editor')\n         super().save(*args, **kwargs)\n \n+    @cached_property\n+    def get_timeline_index(self):\n+        if self.project.display_timeline:\n+            for count, cluster in enumerate(self.project.participation_dates):\n+                if 'event_type' in cluster and self.slug == cluster['slug']:\n+                    return count\n+        return 0\n+\n     def get_absolute_url(self):\n-        return reverse('meinberlin_offlineevents:offlineevent-detail',\n-                       args=[str(self.slug)])\n+        if self.project.display_timeline:\n+            return '{}?initialSlide={}'.format(self.project.get_absolute_url(),\n+                                               self.get_timeline_index)\n+        return self.project.get_absolute_url()\n", "issue": "testing #2252 follow mail: mail participation ends soon\nWhere: Mail \"participation ends soon\"\r\n\r\n* in a single module project link should go to project view and not to a module view that does not regularly exist in this case. Is that possible?\r\n* As in the other mails: paragraph between two sentences probably looks better.\n", "before_files": [{"content": "from datetime import timedelta\n\nfrom autoslug import AutoSlugField\nfrom ckeditor_uploader.fields import RichTextUploadingField\nfrom django.db import models\nfrom django.urls import reverse\nfrom django.utils import timezone\nfrom django.utils.translation import ugettext_lazy as _\n\nfrom adhocracy4 import transforms\nfrom adhocracy4.models.base import UserGeneratedContentModel\nfrom adhocracy4.projects import models as project_models\n\n\nclass OfflineEventsQuerySet(models.QuerySet):\n\n    def starts_within(self, hours=72):\n        \"\"\"All offlineevents starting within the given time.\"\"\"\n        now = timezone.now()\n        return self.filter(date__gt=now,\n                           date__lt=(now + timedelta(hours=hours)))\n\n\nclass OfflineEvent(UserGeneratedContentModel):\n    slug = AutoSlugField(populate_from='name', unique=True)\n    name = models.CharField(max_length=120, verbose_name=_('Name of event'))\n    event_type = models.CharField(\n        max_length=30, verbose_name=_('Event type'),\n        help_text=_('The content of this field is shown in the timeline. It '\n                    'should have no more than 30 characters e.g. Information '\n                    'event or 3rd public workshop.'))\n    date = models.DateTimeField(\n        verbose_name=_('Date'))\n    description = RichTextUploadingField(\n        config_name='image-editor',\n        verbose_name=_('Description'))\n    project = models.ForeignKey(\n        project_models.Project, on_delete=models.CASCADE)\n\n    objects = OfflineEventsQuerySet.as_manager()\n\n    class Meta:\n        ordering = ['-date']\n\n    def __str__(self):\n        return self.name\n\n    def save(self, *args, **kwargs):\n        self.description = transforms.clean_html_field(\n            self.description, 'image-editor')\n        super().save(*args, **kwargs)\n\n    def get_absolute_url(self):\n        return reverse('meinberlin_offlineevents:offlineevent-detail',\n                       args=[str(self.slug)])\n", "path": "meinberlin/apps/offlineevents/models.py"}], "after_files": [{"content": "from datetime import timedelta\n\nfrom autoslug import AutoSlugField\nfrom ckeditor_uploader.fields import RichTextUploadingField\nfrom django.db import models\nfrom django.utils import timezone\nfrom django.utils.functional import cached_property\nfrom django.utils.translation import ugettext_lazy as _\n\nfrom adhocracy4 import transforms\nfrom adhocracy4.models.base import UserGeneratedContentModel\nfrom adhocracy4.projects import models as project_models\n\n\nclass OfflineEventsQuerySet(models.QuerySet):\n\n    def starts_within(self, hours=72):\n        \"\"\"All offlineevents starting within the given time.\"\"\"\n        now = timezone.now()\n        return self.filter(date__gt=now,\n                           date__lt=(now + timedelta(hours=hours)))\n\n\nclass OfflineEvent(UserGeneratedContentModel):\n    slug = AutoSlugField(populate_from='name', unique=True)\n    name = models.CharField(max_length=120, verbose_name=_('Name of event'))\n    event_type = models.CharField(\n        max_length=30, verbose_name=_('Event type'),\n        help_text=_('The content of this field is shown in the timeline. It '\n                    'should have no more than 30 characters e.g. Information '\n                    'event or 3rd public workshop.'))\n    date = models.DateTimeField(\n        verbose_name=_('Date'))\n    description = RichTextUploadingField(\n        config_name='image-editor',\n        verbose_name=_('Description'))\n    project = models.ForeignKey(\n        project_models.Project, on_delete=models.CASCADE)\n\n    objects = OfflineEventsQuerySet.as_manager()\n\n    class Meta:\n        ordering = ['-date']\n\n    def __str__(self):\n        return self.name\n\n    def save(self, *args, **kwargs):\n        self.description = transforms.clean_html_field(\n            self.description, 'image-editor')\n        super().save(*args, **kwargs)\n\n    @cached_property\n    def get_timeline_index(self):\n        if self.project.display_timeline:\n            for count, cluster in enumerate(self.project.participation_dates):\n                if 'event_type' in cluster and self.slug == cluster['slug']:\n                    return count\n        return 0\n\n    def get_absolute_url(self):\n        if self.project.display_timeline:\n            return '{}?initialSlide={}'.format(self.project.get_absolute_url(),\n                                               self.get_timeline_index)\n        return self.project.get_absolute_url()\n", "path": "meinberlin/apps/offlineevents/models.py"}]}