prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  CSV export fails on converting uuid to json
  Problematic JSON structure in https://grand-challenge.org/api/v1/cases/images/redacted_uuid/?format=csv
  
  ```
  {"pk":"redacted_uuid","name":"redacted.png","study":null,"files":[{"pk":"redacted_uuid","image":"redacted_uuid","file":"https://grand-challenge.org/media/images/...mhd","image_type":"MHD"},{"pk":"redacted_uuid","image":"09b3b3d6-0994-43d2-b6a9-eaff634b8805","file":"https://grand-challenge.org/media/images/...zraw","image_type":"MHD"}],"reader_study_set":["https://grand-challenge.org/api/v1/reader-studies/redacted_uuid/","https://grand-challenge.org/api/v1/reader-studies/redacted_uuid/"],"archive_set":[],"job_set":[],"width":596,"height":596,"depth":null,"color_space":"RGB","modality":null,"eye_choice":"NA","stereoscopic_choice":null,"field_of_view":null,"shape_without_color":[596,596],"shape":[596,596,3],"voxel_width_mm":null,"voxel_height_mm":null,"voxel_depth_mm":null,"api_url":"https://grand-challenge.org/api/v1/cases/images/redacted_uuid/"}
  ```
  
  Probably due to trying to serialize the list of files to json in https://github.com/comic/grand-challenge.org/blob/14bc3dd4002756e9cf4a32bb0f238859a9175252/app/grandchallenge/core/renderers.py#L26-L27
  
  --- 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/grandchallenge/core/renderers.py`
  Content:
  ```
  1 import json
  2 
  3 from rest_framework_csv.renderers import CSVRenderer
  4 
  5 
  6 class PaginatedCSVRenderer(CSVRenderer):
  7     results_field = "results"
  8 
  9     def render(self, data, *args, **kwargs):
  10         if self.results_field in data:
  11             data = data[self.results_field]
  12 
  13         return super().render(data, *args, **kwargs)
  14 
  15     def flatten_data(self, data):
  16         """
  17         Create a dictionary that is 1 level deep, with nested values serialized
  18         as json. This means that the header rows are now consistent.
  19         """
  20         for row in data:
  21             flat_row = {k: self._flatten_value(v) for k, v in row.items()}
  22             yield flat_row
  23 
  24     @staticmethod
  25     def _flatten_value(value):
  26         if isinstance(value, (dict, list)):
  27             return json.dumps(value)
  28         else:
  29             return value
  30
  ```
  --- 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()
  
  ```
  
golden_diff: diff --git a/app/grandchallenge/core/renderers.py b/app/grandchallenge/core/renderers.py
  --- a/app/grandchallenge/core/renderers.py
  +++ b/app/grandchallenge/core/renderers.py
  @@ -1,5 +1,7 @@
   import json
   
  +from rest_framework.settings import api_settings
  +from rest_framework.utils.encoders import JSONEncoder
   from rest_framework_csv.renderers import CSVRenderer
   
   
  @@ -24,6 +26,11 @@
       @staticmethod
       def _flatten_value(value):
           if isinstance(value, (dict, list)):
  -            return json.dumps(value)
  +            return json.dumps(
  +                value,
  +                cls=JSONEncoder,
  +                ensure_ascii=not api_settings.UNICODE_JSON,
  +                allow_nan=not api_settings.STRICT_JSON,
  +            )
           else:
               return value
  
verification_info: {"golden_diff": "diff --git a/app/grandchallenge/core/renderers.py b/app/grandchallenge/core/renderers.py\n--- a/app/grandchallenge/core/renderers.py\n+++ b/app/grandchallenge/core/renderers.py\n@@ -1,5 +1,7 @@\n import json\n \n+from rest_framework.settings import api_settings\n+from rest_framework.utils.encoders import JSONEncoder\n from rest_framework_csv.renderers import CSVRenderer\n \n \n@@ -24,6 +26,11 @@\n     @staticmethod\n     def _flatten_value(value):\n         if isinstance(value, (dict, list)):\n-            return json.dumps(value)\n+            return json.dumps(\n+                value,\n+                cls=JSONEncoder,\n+                ensure_ascii=not api_settings.UNICODE_JSON,\n+                allow_nan=not api_settings.STRICT_JSON,\n+            )\n         else:\n             return value\n", "issue": "CSV export fails on converting uuid to json\nProblematic JSON structure in https://grand-challenge.org/api/v1/cases/images/redacted_uuid/?format=csv\r\n\r\n```\r\n{\"pk\":\"redacted_uuid\",\"name\":\"redacted.png\",\"study\":null,\"files\":[{\"pk\":\"redacted_uuid\",\"image\":\"redacted_uuid\",\"file\":\"https://grand-challenge.org/media/images/...mhd\",\"image_type\":\"MHD\"},{\"pk\":\"redacted_uuid\",\"image\":\"09b3b3d6-0994-43d2-b6a9-eaff634b8805\",\"file\":\"https://grand-challenge.org/media/images/...zraw\",\"image_type\":\"MHD\"}],\"reader_study_set\":[\"https://grand-challenge.org/api/v1/reader-studies/redacted_uuid/\",\"https://grand-challenge.org/api/v1/reader-studies/redacted_uuid/\"],\"archive_set\":[],\"job_set\":[],\"width\":596,\"height\":596,\"depth\":null,\"color_space\":\"RGB\",\"modality\":null,\"eye_choice\":\"NA\",\"stereoscopic_choice\":null,\"field_of_view\":null,\"shape_without_color\":[596,596],\"shape\":[596,596,3],\"voxel_width_mm\":null,\"voxel_height_mm\":null,\"voxel_depth_mm\":null,\"api_url\":\"https://grand-challenge.org/api/v1/cases/images/redacted_uuid/\"}\r\n```\r\n\r\nProbably due to trying to serialize the list of files to json in https://github.com/comic/grand-challenge.org/blob/14bc3dd4002756e9cf4a32bb0f238859a9175252/app/grandchallenge/core/renderers.py#L26-L27\n", "before_files": [{"content": "import json\n\nfrom rest_framework_csv.renderers import CSVRenderer\n\n\nclass PaginatedCSVRenderer(CSVRenderer):\n    results_field = \"results\"\n\n    def render(self, data, *args, **kwargs):\n        if self.results_field in data:\n            data = data[self.results_field]\n\n        return super().render(data, *args, **kwargs)\n\n    def flatten_data(self, data):\n        \"\"\"\n        Create a dictionary that is 1 level deep, with nested values serialized\n        as json. This means that the header rows are now consistent.\n        \"\"\"\n        for row in data:\n            flat_row = {k: self._flatten_value(v) for k, v in row.items()}\n            yield flat_row\n\n    @staticmethod\n    def _flatten_value(value):\n        if isinstance(value, (dict, list)):\n            return json.dumps(value)\n        else:\n            return value\n", "path": "app/grandchallenge/core/renderers.py"}], "after_files": [{"content": "import json\n\nfrom rest_framework.settings import api_settings\nfrom rest_framework.utils.encoders import JSONEncoder\nfrom rest_framework_csv.renderers import CSVRenderer\n\n\nclass PaginatedCSVRenderer(CSVRenderer):\n    results_field = \"results\"\n\n    def render(self, data, *args, **kwargs):\n        if self.results_field in data:\n            data = data[self.results_field]\n\n        return super().render(data, *args, **kwargs)\n\n    def flatten_data(self, data):\n        \"\"\"\n        Create a dictionary that is 1 level deep, with nested values serialized\n        as json. This means that the header rows are now consistent.\n        \"\"\"\n        for row in data:\n            flat_row = {k: self._flatten_value(v) for k, v in row.items()}\n            yield flat_row\n\n    @staticmethod\n    def _flatten_value(value):\n        if isinstance(value, (dict, list)):\n            return json.dumps(\n                value,\n                cls=JSONEncoder,\n                ensure_ascii=not api_settings.UNICODE_JSON,\n                allow_nan=not api_settings.STRICT_JSON,\n            )\n        else:\n            return value\n", "path": "app/grandchallenge/core/renderers.py"}]}