We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Remove version model
**Describe the bug**
The version model is not used currently and should be removed

https://github.com/fossasia/open-event-server/blob/development/app/models/version.py


**Additional context**
@iamareebjamal Taking this


--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `app/models/version.py`
Content:
```
1 from sqlalchemy.orm import backref
2 
3 from app.models import db
4 
5 
6 class Version(db.Model):
7     """Version model class"""
8     __tablename__ = 'versions'
9     id = db.Column(db.Integer, primary_key=True)
10     event_id = db.Column(db.Integer, db.ForeignKey('events.id', ondelete='CASCADE'))
11     events = db.relationship("Event", backref=backref('version', uselist=False))
12 
13     event_ver = db.Column(db.Integer, nullable=False, default=0)
14     sessions_ver = db.Column(db.Integer, nullable=False, default=0)
15     speakers_ver = db.Column(db.Integer, nullable=False, default=0)
16     tracks_ver = db.Column(db.Integer, nullable=False, default=0)
17     sponsors_ver = db.Column(db.Integer, nullable=False, default=0)
18     microlocations_ver = db.Column(db.Integer, nullable=False, default=0)
19 
20     def __init__(self,
21                  event_id=None,
22                  event_ver=None,
23                  sessions_ver=None,
24                  speakers_ver=None,
25                  tracks_ver=None,
26                  sponsors_ver=None,
27                  microlocations_ver=None):
28         self.event_id = event_id
29         self.event_ver = event_ver
30         self.sessions_ver = sessions_ver
31         self.speakers_ver = speakers_ver
32         self.tracks_ver = tracks_ver
33         self.sponsors_ver = sponsors_ver
34         self.microlocations_ver = microlocations_ver
35 
36     def __repr__(self):
37         return '<Version %r>' % self.id
38 
39     def __str__(self):
40         return self.__repr__()
41 
42     @property
43     def serialize(self):
44         """Return object data in easily serializable format"""
45         return {
46             'version': [
47                 {'id': self.id,
48                  'event_id': self.event_id,
49                  'event_ver': self.event_ver,
50                  'sessions_ver': self.sessions_ver,
51                  'speakers_ver': self.speakers_ver,
52                  'tracks_ver': self.tracks_ver,
53                  'sponsors_ver': self.sponsors_ver,
54                  'microlocations_ver': self.microlocations_ver}
55             ]
56         }
57
```
--- 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/app/models/version.py b/app/models/version.py
deleted file mode 100644
--- a/app/models/version.py
+++ /dev/null
@@ -1,56 +0,0 @@
-from sqlalchemy.orm import backref
-
-from app.models import db
-
-
-class Version(db.Model):
-    """Version model class"""
-    __tablename__ = 'versions'
-    id = db.Column(db.Integer, primary_key=True)
-    event_id = db.Column(db.Integer, db.ForeignKey('events.id', ondelete='CASCADE'))
-    events = db.relationship("Event", backref=backref('version', uselist=False))
-
-    event_ver = db.Column(db.Integer, nullable=False, default=0)
-    sessions_ver = db.Column(db.Integer, nullable=False, default=0)
-    speakers_ver = db.Column(db.Integer, nullable=False, default=0)
-    tracks_ver = db.Column(db.Integer, nullable=False, default=0)
-    sponsors_ver = db.Column(db.Integer, nullable=False, default=0)
-    microlocations_ver = db.Column(db.Integer, nullable=False, default=0)
-
-    def __init__(self,
-                 event_id=None,
-                 event_ver=None,
-                 sessions_ver=None,
-                 speakers_ver=None,
-                 tracks_ver=None,
-                 sponsors_ver=None,
-                 microlocations_ver=None):
-        self.event_id = event_id
-        self.event_ver = event_ver
-        self.sessions_ver = sessions_ver
-        self.speakers_ver = speakers_ver
-        self.tracks_ver = tracks_ver
-        self.sponsors_ver = sponsors_ver
-        self.microlocations_ver = microlocations_ver
-
-    def __repr__(self):
-        return '<Version %r>' % self.id
-
-    def __str__(self):
-        return self.__repr__()
-
-    @property
-    def serialize(self):
-        """Return object data in easily serializable format"""
-        return {
-            'version': [
-                {'id': self.id,
-                 'event_id': self.event_id,
-                 'event_ver': self.event_ver,
-                 'sessions_ver': self.sessions_ver,
-                 'speakers_ver': self.speakers_ver,
-                 'tracks_ver': self.tracks_ver,
-                 'sponsors_ver': self.sponsors_ver,
-                 'microlocations_ver': self.microlocations_ver}
-            ]
-        }

{"golden_diff": "diff --git a/app/models/version.py b/app/models/version.py\ndeleted file mode 100644\n--- a/app/models/version.py\n+++ /dev/null\n@@ -1,56 +0,0 @@\n-from sqlalchemy.orm import backref\n-\n-from app.models import db\n-\n-\n-class Version(db.Model):\n-    \"\"\"Version model class\"\"\"\n-    __tablename__ = 'versions'\n-    id = db.Column(db.Integer, primary_key=True)\n-    event_id = db.Column(db.Integer, db.ForeignKey('events.id', ondelete='CASCADE'))\n-    events = db.relationship(\"Event\", backref=backref('version', uselist=False))\n-\n-    event_ver = db.Column(db.Integer, nullable=False, default=0)\n-    sessions_ver = db.Column(db.Integer, nullable=False, default=0)\n-    speakers_ver = db.Column(db.Integer, nullable=False, default=0)\n-    tracks_ver = db.Column(db.Integer, nullable=False, default=0)\n-    sponsors_ver = db.Column(db.Integer, nullable=False, default=0)\n-    microlocations_ver = db.Column(db.Integer, nullable=False, default=0)\n-\n-    def __init__(self,\n-                 event_id=None,\n-                 event_ver=None,\n-                 sessions_ver=None,\n-                 speakers_ver=None,\n-                 tracks_ver=None,\n-                 sponsors_ver=None,\n-                 microlocations_ver=None):\n-        self.event_id = event_id\n-        self.event_ver = event_ver\n-        self.sessions_ver = sessions_ver\n-        self.speakers_ver = speakers_ver\n-        self.tracks_ver = tracks_ver\n-        self.sponsors_ver = sponsors_ver\n-        self.microlocations_ver = microlocations_ver\n-\n-    def __repr__(self):\n-        return '<Version %r>' % self.id\n-\n-    def __str__(self):\n-        return self.__repr__()\n-\n-    @property\n-    def serialize(self):\n-        \"\"\"Return object data in easily serializable format\"\"\"\n-        return {\n-            'version': [\n-                {'id': self.id,\n-                 'event_id': self.event_id,\n-                 'event_ver': self.event_ver,\n-                 'sessions_ver': self.sessions_ver,\n-                 'speakers_ver': self.speakers_ver,\n-                 'tracks_ver': self.tracks_ver,\n-                 'sponsors_ver': self.sponsors_ver,\n-                 'microlocations_ver': self.microlocations_ver}\n-            ]\n-        }\n", "issue": "Remove version model\n**Describe the bug**\r\nThe version model is not used currently and should be removed\r\n\r\nhttps://github.com/fossasia/open-event-server/blob/development/app/models/version.py\r\n\r\n\r\n**Additional context**\r\n@iamareebjamal Taking this\r\n\n", "before_files": [{"content": "from sqlalchemy.orm import backref\n\nfrom app.models import db\n\n\nclass Version(db.Model):\n    \"\"\"Version model class\"\"\"\n    __tablename__ = 'versions'\n    id = db.Column(db.Integer, primary_key=True)\n    event_id = db.Column(db.Integer, db.ForeignKey('events.id', ondelete='CASCADE'))\n    events = db.relationship(\"Event\", backref=backref('version', uselist=False))\n\n    event_ver = db.Column(db.Integer, nullable=False, default=0)\n    sessions_ver = db.Column(db.Integer, nullable=False, default=0)\n    speakers_ver = db.Column(db.Integer, nullable=False, default=0)\n    tracks_ver = db.Column(db.Integer, nullable=False, default=0)\n    sponsors_ver = db.Column(db.Integer, nullable=False, default=0)\n    microlocations_ver = db.Column(db.Integer, nullable=False, default=0)\n\n    def __init__(self,\n                 event_id=None,\n                 event_ver=None,\n                 sessions_ver=None,\n                 speakers_ver=None,\n                 tracks_ver=None,\n                 sponsors_ver=None,\n                 microlocations_ver=None):\n        self.event_id = event_id\n        self.event_ver = event_ver\n        self.sessions_ver = sessions_ver\n        self.speakers_ver = speakers_ver\n        self.tracks_ver = tracks_ver\n        self.sponsors_ver = sponsors_ver\n        self.microlocations_ver = microlocations_ver\n\n    def __repr__(self):\n        return '<Version %r>' % self.id\n\n    def __str__(self):\n        return self.__repr__()\n\n    @property\n    def serialize(self):\n        \"\"\"Return object data in easily serializable format\"\"\"\n        return {\n            'version': [\n                {'id': self.id,\n                 'event_id': self.event_id,\n                 'event_ver': self.event_ver,\n                 'sessions_ver': self.sessions_ver,\n                 'speakers_ver': self.speakers_ver,\n                 'tracks_ver': self.tracks_ver,\n                 'sponsors_ver': self.sponsors_ver,\n                 'microlocations_ver': self.microlocations_ver}\n            ]\n        }\n", "path": "app/models/version.py"}], "after_files": [{"content": null, "path": "app/models/version.py"}]}