prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  [BUG] Exception when property of patched_fig is viewed
  I know that it is currently not supported to view properties of `patch_fig=Patch()` but when e.g. iterating over trace names like so:
  ```
   for trace in patched_fig['data']:
          print(trace['name'])
  ```
  no exception or error message is thrown but an endless stream of 
  
  ```
  ...
  <dash._patch.Patch object at 0x7f3b89a89b80>
  <dash._patch.Patch object at 0x7f3b8305c0a0>
  <dash._patch.Patch object at 0x7f3b89a89b80>
  <dash._patch.Patch object at 0x7f3b8305c0a0>
  <dash._patch.Patch object at 0x7f3b89a89b80>
  <dash._patch.Patch object at 0x7f3b8305c0a0>
  ...
  ```
  This is not exactly intended right?
  
  I got there by trying to delete a trace of patched_fig by its name which otherwise appears not be possible (or is it?)
  
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `dash/_patch.py`
  Content:
  ```
  1 def _operation(name, location, **kwargs):
  2     return {"operation": name, "location": location, "params": dict(**kwargs)}
  3 
  4 
  5 _noop = object()
  6 
  7 
  8 def validate_slice(obj):
  9     if isinstance(obj, slice):
  10         raise TypeError("a slice is not a valid index for patch")
  11 
  12 
  13 class Patch:
  14     """
  15     Patch a callback output value
  16 
  17     Act like a proxy of the output prop value on the frontend.
  18 
  19     Supported prop types: Dictionaries and lists.
  20     """
  21 
  22     def __init__(self, location=None, parent=None):
  23         if location is not None:
  24             self._location = location
  25         else:
  26             # pylint: disable=consider-using-ternary
  27             self._location = (parent and parent._location) or []
  28         if parent is not None:
  29             self._operations = parent._operations
  30         else:
  31             self._operations = []
  32 
  33     def __getstate__(self):
  34         return vars(self)
  35 
  36     def __setstate__(self, state):
  37         vars(self).update(state)
  38 
  39     def __getitem__(self, item):
  40         validate_slice(item)
  41         return Patch(location=self._location + [item], parent=self)
  42 
  43     def __getattr__(self, item):
  44         if item == "tolist":
  45             # to_json fix
  46             raise AttributeError
  47         if item == "_location":
  48             return self._location
  49         if item == "_operations":
  50             return self._operations
  51         return self.__getitem__(item)
  52 
  53     def __setattr__(self, key, value):
  54         if key in ("_location", "_operations"):
  55             self.__dict__[key] = value
  56         else:
  57             self.__setitem__(key, value)
  58 
  59     def __delattr__(self, item):
  60         self.__delitem__(item)
  61 
  62     def __setitem__(self, key, value):
  63         validate_slice(key)
  64         if value is _noop:
  65             # The += set themselves.
  66             return
  67         self._operations.append(
  68             _operation(
  69                 "Assign",
  70                 self._location + [key],
  71                 value=value,
  72             )
  73         )
  74 
  75     def __delitem__(self, key):
  76         validate_slice(key)
  77         self._operations.append(_operation("Delete", self._location + [key]))
  78 
  79     def __iadd__(self, other):
  80         if isinstance(other, (list, tuple)):
  81             self.extend(other)
  82         else:
  83             self._operations.append(_operation("Add", self._location, value=other))
  84         return _noop
  85 
  86     def __isub__(self, other):
  87         self._operations.append(_operation("Sub", self._location, value=other))
  88         return _noop
  89 
  90     def __imul__(self, other):
  91         self._operations.append(_operation("Mul", self._location, value=other))
  92         return _noop
  93 
  94     def __itruediv__(self, other):
  95         self._operations.append(_operation("Div", self._location, value=other))
  96         return _noop
  97 
  98     def __ior__(self, other):
  99         self.update(E=other)
  100         return _noop
  101 
  102     def append(self, item):
  103         """Add the item to the end of a list"""
  104         self._operations.append(_operation("Append", self._location, value=item))
  105 
  106     def prepend(self, item):
  107         """Add the item to the start of a list"""
  108         self._operations.append(_operation("Prepend", self._location, value=item))
  109 
  110     def insert(self, index, item):
  111         """Add the item at the index of a list"""
  112         self._operations.append(
  113             _operation("Insert", self._location, value=item, index=index)
  114         )
  115 
  116     def clear(self):
  117         """Remove all items in a list"""
  118         self._operations.append(_operation("Clear", self._location))
  119 
  120     def reverse(self):
  121         """Reversal of the order of items in a list"""
  122         self._operations.append(_operation("Reverse", self._location))
  123 
  124     def extend(self, item):
  125         """Add all the items to the end of a list"""
  126         if not isinstance(item, (list, tuple)):
  127             raise TypeError(f"{item} should be a list or tuple")
  128         self._operations.append(_operation("Extend", self._location, value=item))
  129 
  130     def remove(self, item):
  131         """filter the item out of a list on the frontend"""
  132         self._operations.append(_operation("Remove", self._location, value=item))
  133 
  134     def update(self, E=None, **F):
  135         """Merge a dict or keyword arguments with another dictionary"""
  136         value = E or {}
  137         value.update(F)
  138         self._operations.append(_operation("Merge", self._location, value=value))
  139 
  140     # pylint: disable=no-self-use
  141     def sort(self):
  142         raise KeyError(
  143             "sort is reserved for future use, use brackets to access this key on your object"
  144         )
  145 
  146     def to_plotly_json(self):
  147         return {
  148             "__dash_patch_update": "__dash_patch_update",
  149             "operations": self._operations,
  150         }
  151
  ```
  --- 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/dash/_patch.py b/dash/_patch.py
  --- a/dash/_patch.py
  +++ b/dash/_patch.py
  @@ -99,6 +99,12 @@
           self.update(E=other)
           return _noop
   
  +    def __iter__(self):
  +        raise TypeError("Patch objects are write-only, you cannot iterate them.")
  +
  +    def __repr__(self):
  +        return f"<write-only dash.Patch object at {self._location}>"
  +
       def append(self, item):
           """Add the item to the end of a list"""
           self._operations.append(_operation("Append", self._location, value=item))
  
verification_info: {"golden_diff": "diff --git a/dash/_patch.py b/dash/_patch.py\n--- a/dash/_patch.py\n+++ b/dash/_patch.py\n@@ -99,6 +99,12 @@\n         self.update(E=other)\n         return _noop\n \n+    def __iter__(self):\n+        raise TypeError(\"Patch objects are write-only, you cannot iterate them.\")\n+\n+    def __repr__(self):\n+        return f\"<write-only dash.Patch object at {self._location}>\"\n+\n     def append(self, item):\n         \"\"\"Add the item to the end of a list\"\"\"\n         self._operations.append(_operation(\"Append\", self._location, value=item))\n", "issue": "[BUG] Exception when property of patched_fig is viewed\nI know that it is currently not supported to view properties of `patch_fig=Patch()` but when e.g. iterating over trace names like so:\r\n```\r\n for trace in patched_fig['data']:\r\n        print(trace['name'])\r\n```\r\nno exception or error message is thrown but an endless stream of \r\n\r\n```\r\n...\r\n<dash._patch.Patch object at 0x7f3b89a89b80>\r\n<dash._patch.Patch object at 0x7f3b8305c0a0>\r\n<dash._patch.Patch object at 0x7f3b89a89b80>\r\n<dash._patch.Patch object at 0x7f3b8305c0a0>\r\n<dash._patch.Patch object at 0x7f3b89a89b80>\r\n<dash._patch.Patch object at 0x7f3b8305c0a0>\r\n...\r\n```\r\nThis is not exactly intended right?\r\n\r\nI got there by trying to delete a trace of patched_fig by its name which otherwise appears not be possible (or is it?)\r\n\n", "before_files": [{"content": "def _operation(name, location, **kwargs):\n    return {\"operation\": name, \"location\": location, \"params\": dict(**kwargs)}\n\n\n_noop = object()\n\n\ndef validate_slice(obj):\n    if isinstance(obj, slice):\n        raise TypeError(\"a slice is not a valid index for patch\")\n\n\nclass Patch:\n    \"\"\"\n    Patch a callback output value\n\n    Act like a proxy of the output prop value on the frontend.\n\n    Supported prop types: Dictionaries and lists.\n    \"\"\"\n\n    def __init__(self, location=None, parent=None):\n        if location is not None:\n            self._location = location\n        else:\n            # pylint: disable=consider-using-ternary\n            self._location = (parent and parent._location) or []\n        if parent is not None:\n            self._operations = parent._operations\n        else:\n            self._operations = []\n\n    def __getstate__(self):\n        return vars(self)\n\n    def __setstate__(self, state):\n        vars(self).update(state)\n\n    def __getitem__(self, item):\n        validate_slice(item)\n        return Patch(location=self._location + [item], parent=self)\n\n    def __getattr__(self, item):\n        if item == \"tolist\":\n            # to_json fix\n            raise AttributeError\n        if item == \"_location\":\n            return self._location\n        if item == \"_operations\":\n            return self._operations\n        return self.__getitem__(item)\n\n    def __setattr__(self, key, value):\n        if key in (\"_location\", \"_operations\"):\n            self.__dict__[key] = value\n        else:\n            self.__setitem__(key, value)\n\n    def __delattr__(self, item):\n        self.__delitem__(item)\n\n    def __setitem__(self, key, value):\n        validate_slice(key)\n        if value is _noop:\n            # The += set themselves.\n            return\n        self._operations.append(\n            _operation(\n                \"Assign\",\n                self._location + [key],\n                value=value,\n            )\n        )\n\n    def __delitem__(self, key):\n        validate_slice(key)\n        self._operations.append(_operation(\"Delete\", self._location + [key]))\n\n    def __iadd__(self, other):\n        if isinstance(other, (list, tuple)):\n            self.extend(other)\n        else:\n            self._operations.append(_operation(\"Add\", self._location, value=other))\n        return _noop\n\n    def __isub__(self, other):\n        self._operations.append(_operation(\"Sub\", self._location, value=other))\n        return _noop\n\n    def __imul__(self, other):\n        self._operations.append(_operation(\"Mul\", self._location, value=other))\n        return _noop\n\n    def __itruediv__(self, other):\n        self._operations.append(_operation(\"Div\", self._location, value=other))\n        return _noop\n\n    def __ior__(self, other):\n        self.update(E=other)\n        return _noop\n\n    def append(self, item):\n        \"\"\"Add the item to the end of a list\"\"\"\n        self._operations.append(_operation(\"Append\", self._location, value=item))\n\n    def prepend(self, item):\n        \"\"\"Add the item to the start of a list\"\"\"\n        self._operations.append(_operation(\"Prepend\", self._location, value=item))\n\n    def insert(self, index, item):\n        \"\"\"Add the item at the index of a list\"\"\"\n        self._operations.append(\n            _operation(\"Insert\", self._location, value=item, index=index)\n        )\n\n    def clear(self):\n        \"\"\"Remove all items in a list\"\"\"\n        self._operations.append(_operation(\"Clear\", self._location))\n\n    def reverse(self):\n        \"\"\"Reversal of the order of items in a list\"\"\"\n        self._operations.append(_operation(\"Reverse\", self._location))\n\n    def extend(self, item):\n        \"\"\"Add all the items to the end of a list\"\"\"\n        if not isinstance(item, (list, tuple)):\n            raise TypeError(f\"{item} should be a list or tuple\")\n        self._operations.append(_operation(\"Extend\", self._location, value=item))\n\n    def remove(self, item):\n        \"\"\"filter the item out of a list on the frontend\"\"\"\n        self._operations.append(_operation(\"Remove\", self._location, value=item))\n\n    def update(self, E=None, **F):\n        \"\"\"Merge a dict or keyword arguments with another dictionary\"\"\"\n        value = E or {}\n        value.update(F)\n        self._operations.append(_operation(\"Merge\", self._location, value=value))\n\n    # pylint: disable=no-self-use\n    def sort(self):\n        raise KeyError(\n            \"sort is reserved for future use, use brackets to access this key on your object\"\n        )\n\n    def to_plotly_json(self):\n        return {\n            \"__dash_patch_update\": \"__dash_patch_update\",\n            \"operations\": self._operations,\n        }\n", "path": "dash/_patch.py"}], "after_files": [{"content": "def _operation(name, location, **kwargs):\n    return {\"operation\": name, \"location\": location, \"params\": dict(**kwargs)}\n\n\n_noop = object()\n\n\ndef validate_slice(obj):\n    if isinstance(obj, slice):\n        raise TypeError(\"a slice is not a valid index for patch\")\n\n\nclass Patch:\n    \"\"\"\n    Patch a callback output value\n\n    Act like a proxy of the output prop value on the frontend.\n\n    Supported prop types: Dictionaries and lists.\n    \"\"\"\n\n    def __init__(self, location=None, parent=None):\n        if location is not None:\n            self._location = location\n        else:\n            # pylint: disable=consider-using-ternary\n            self._location = (parent and parent._location) or []\n        if parent is not None:\n            self._operations = parent._operations\n        else:\n            self._operations = []\n\n    def __getstate__(self):\n        return vars(self)\n\n    def __setstate__(self, state):\n        vars(self).update(state)\n\n    def __getitem__(self, item):\n        validate_slice(item)\n        return Patch(location=self._location + [item], parent=self)\n\n    def __getattr__(self, item):\n        if item == \"tolist\":\n            # to_json fix\n            raise AttributeError\n        if item == \"_location\":\n            return self._location\n        if item == \"_operations\":\n            return self._operations\n        return self.__getitem__(item)\n\n    def __setattr__(self, key, value):\n        if key in (\"_location\", \"_operations\"):\n            self.__dict__[key] = value\n        else:\n            self.__setitem__(key, value)\n\n    def __delattr__(self, item):\n        self.__delitem__(item)\n\n    def __setitem__(self, key, value):\n        validate_slice(key)\n        if value is _noop:\n            # The += set themselves.\n            return\n        self._operations.append(\n            _operation(\n                \"Assign\",\n                self._location + [key],\n                value=value,\n            )\n        )\n\n    def __delitem__(self, key):\n        validate_slice(key)\n        self._operations.append(_operation(\"Delete\", self._location + [key]))\n\n    def __iadd__(self, other):\n        if isinstance(other, (list, tuple)):\n            self.extend(other)\n        else:\n            self._operations.append(_operation(\"Add\", self._location, value=other))\n        return _noop\n\n    def __isub__(self, other):\n        self._operations.append(_operation(\"Sub\", self._location, value=other))\n        return _noop\n\n    def __imul__(self, other):\n        self._operations.append(_operation(\"Mul\", self._location, value=other))\n        return _noop\n\n    def __itruediv__(self, other):\n        self._operations.append(_operation(\"Div\", self._location, value=other))\n        return _noop\n\n    def __ior__(self, other):\n        self.update(E=other)\n        return _noop\n\n    def __iter__(self):\n        raise TypeError(\"Patch objects are write-only, you cannot iterate them.\")\n\n    def __repr__(self):\n        return f\"<write-only dash.Patch object at {self._location}>\"\n\n    def append(self, item):\n        \"\"\"Add the item to the end of a list\"\"\"\n        self._operations.append(_operation(\"Append\", self._location, value=item))\n\n    def prepend(self, item):\n        \"\"\"Add the item to the start of a list\"\"\"\n        self._operations.append(_operation(\"Prepend\", self._location, value=item))\n\n    def insert(self, index, item):\n        \"\"\"Add the item at the index of a list\"\"\"\n        self._operations.append(\n            _operation(\"Insert\", self._location, value=item, index=index)\n        )\n\n    def clear(self):\n        \"\"\"Remove all items in a list\"\"\"\n        self._operations.append(_operation(\"Clear\", self._location))\n\n    def reverse(self):\n        \"\"\"Reversal of the order of items in a list\"\"\"\n        self._operations.append(_operation(\"Reverse\", self._location))\n\n    def extend(self, item):\n        \"\"\"Add all the items to the end of a list\"\"\"\n        if not isinstance(item, (list, tuple)):\n            raise TypeError(f\"{item} should be a list or tuple\")\n        self._operations.append(_operation(\"Extend\", self._location, value=item))\n\n    def remove(self, item):\n        \"\"\"filter the item out of a list on the frontend\"\"\"\n        self._operations.append(_operation(\"Remove\", self._location, value=item))\n\n    def update(self, E=None, **F):\n        \"\"\"Merge a dict or keyword arguments with another dictionary\"\"\"\n        value = E or {}\n        value.update(F)\n        self._operations.append(_operation(\"Merge\", self._location, value=value))\n\n    # pylint: disable=no-self-use\n    def sort(self):\n        raise KeyError(\n            \"sort is reserved for future use, use brackets to access this key on your object\"\n        )\n\n    def to_plotly_json(self):\n        return {\n            \"__dash_patch_update\": \"__dash_patch_update\",\n            \"operations\": self._operations,\n        }\n", "path": "dash/_patch.py"}]}