We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Add information about Dataset to Tasks endpoint
## Current Behavior

Tasks endpoint returns list of all Tasks **without** information about their Datasets.

## Expected Behavior

Each Task returned by this endpoint should also contain information about its Dataset.

## Tasks to do

- [ ] Add Dataset key to the Task returned by Tasks endpoint.

## Additional comment

Dataset key will be fine only if there will be an endpoint that will return all Datasets available in MedTagger.

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `backend/medtagger/api/tasks/serializers.py`
Content:
```
1 """Module responsible for storage of serializers used in Tasks endpoints."""
2 from flask_restplus import fields
3 
4 from medtagger.api import api
5 from medtagger.definitions import LabelTool
6 
7 out__label_tag = api.model('Label Tag model', {
8     'key': fields.String(),
9     'name': fields.String(),
10     'actions_ids': fields.List(fields.Integer(),
11                                attribute=lambda label_tag: [action.id for action in label_tag.actions]),
12     'tools': fields.List(fields.String(), description='Available tools for Label Tag',
13                          enum=[tool.name for tool in LabelTool],
14                          attribute=lambda label_tag: [tool.name for tool in label_tag.tools]),
15 })
16 
17 in__label_tag = api.model('Label Tag model', {
18     'key': fields.String(),
19     'name': fields.String(),
20     'actions_ids': fields.List(fields.Integer()),
21     'tools': fields.List(fields.String(), description='Available tools for Label Tag',
22                          enum=[tool.name for tool in LabelTool]),
23 })
24 
25 out__task = api.model('Task model', {
26     'key': fields.String(),
27     'name': fields.String(),
28     'image_path': fields.String(),
29     'tags': fields.List(fields.Nested(out__label_tag), attribute='available_tags'),
30 })
31 
32 in__task = api.model('New Task model', {
33     'key': fields.String(),
34     'name': fields.String(),
35     'image_path': fields.String(),
36     'datasets_keys': fields.List(fields.String()),
37     'tags': fields.List(fields.Nested(in__label_tag), attribute='available_tags'),
38 })
39
```
--- 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/backend/medtagger/api/tasks/serializers.py b/backend/medtagger/api/tasks/serializers.py
--- a/backend/medtagger/api/tasks/serializers.py
+++ b/backend/medtagger/api/tasks/serializers.py
@@ -27,6 +27,7 @@
     'name': fields.String(),
     'image_path': fields.String(),
     'tags': fields.List(fields.Nested(out__label_tag), attribute='available_tags'),
+    'datasets_keys': fields.List(fields.String(), attribute=lambda task: [dataset.key for dataset in task.datasets]),
 })
 
 in__task = api.model('New Task model', {

{"golden_diff": "diff --git a/backend/medtagger/api/tasks/serializers.py b/backend/medtagger/api/tasks/serializers.py\n--- a/backend/medtagger/api/tasks/serializers.py\n+++ b/backend/medtagger/api/tasks/serializers.py\n@@ -27,6 +27,7 @@\n     'name': fields.String(),\n     'image_path': fields.String(),\n     'tags': fields.List(fields.Nested(out__label_tag), attribute='available_tags'),\n+    'datasets_keys': fields.List(fields.String(), attribute=lambda task: [dataset.key for dataset in task.datasets]),\n })\n \n in__task = api.model('New Task model', {\n", "issue": "Add information about Dataset to Tasks endpoint\n## Current Behavior\r\n\r\nTasks endpoint returns list of all Tasks **without** information about their Datasets.\r\n\r\n## Expected Behavior\r\n\r\nEach Task returned by this endpoint should also contain information about its Dataset.\r\n\r\n## Tasks to do\r\n\r\n- [ ] Add Dataset key to the Task returned by Tasks endpoint.\r\n\r\n## Additional comment\r\n\r\nDataset key will be fine only if there will be an endpoint that will return all Datasets available in MedTagger.\n", "before_files": [{"content": "\"\"\"Module responsible for storage of serializers used in Tasks endpoints.\"\"\"\nfrom flask_restplus import fields\n\nfrom medtagger.api import api\nfrom medtagger.definitions import LabelTool\n\nout__label_tag = api.model('Label Tag model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'actions_ids': fields.List(fields.Integer(),\n                               attribute=lambda label_tag: [action.id for action in label_tag.actions]),\n    'tools': fields.List(fields.String(), description='Available tools for Label Tag',\n                         enum=[tool.name for tool in LabelTool],\n                         attribute=lambda label_tag: [tool.name for tool in label_tag.tools]),\n})\n\nin__label_tag = api.model('Label Tag model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'actions_ids': fields.List(fields.Integer()),\n    'tools': fields.List(fields.String(), description='Available tools for Label Tag',\n                         enum=[tool.name for tool in LabelTool]),\n})\n\nout__task = api.model('Task model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'image_path': fields.String(),\n    'tags': fields.List(fields.Nested(out__label_tag), attribute='available_tags'),\n})\n\nin__task = api.model('New Task model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'image_path': fields.String(),\n    'datasets_keys': fields.List(fields.String()),\n    'tags': fields.List(fields.Nested(in__label_tag), attribute='available_tags'),\n})\n", "path": "backend/medtagger/api/tasks/serializers.py"}], "after_files": [{"content": "\"\"\"Module responsible for storage of serializers used in Tasks endpoints.\"\"\"\nfrom flask_restplus import fields\n\nfrom medtagger.api import api\nfrom medtagger.definitions import LabelTool\n\nout__label_tag = api.model('Label Tag model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'actions_ids': fields.List(fields.Integer(),\n                               attribute=lambda label_tag: [action.id for action in label_tag.actions]),\n    'tools': fields.List(fields.String(), description='Available tools for Label Tag',\n                         enum=[tool.name for tool in LabelTool],\n                         attribute=lambda label_tag: [tool.name for tool in label_tag.tools]),\n})\n\nin__label_tag = api.model('Label Tag model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'actions_ids': fields.List(fields.Integer()),\n    'tools': fields.List(fields.String(), description='Available tools for Label Tag',\n                         enum=[tool.name for tool in LabelTool]),\n})\n\nout__task = api.model('Task model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'image_path': fields.String(),\n    'tags': fields.List(fields.Nested(out__label_tag), attribute='available_tags'),\n    'datasets_keys': fields.List(fields.String(), attribute=lambda task: [dataset.key for dataset in task.datasets]),\n})\n\nin__task = api.model('New Task model', {\n    'key': fields.String(),\n    'name': fields.String(),\n    'image_path': fields.String(),\n    'datasets_keys': fields.List(fields.String()),\n    'tags': fields.List(fields.Nested(in__label_tag), attribute='available_tags'),\n})\n", "path": "backend/medtagger/api/tasks/serializers.py"}]}