We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
[BUG] Patch += operation not working on the patch object.
If you have a patch object for a number prop and try to do `patched += 1`,  the callback will fail with an error, `returned non serializable object`.

Example:
```
app = Dash()
app.layout = [dcc.Store(data=0, store="store"), html.Button("click", id="click")]
@app.callback(Output("store", "data"), Input("click", "n_clicks"))
def on_click(_):
    patched = Patch()
    patched += 1
    return patched
```

Clicking on the button result in the error, it should instead update the store data prop to +1.

--- 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 __iter__(self):
103         raise TypeError("Patch objects are write-only, you cannot iterate them.")
104 
105     def __repr__(self):
106         return f"<write-only dash.Patch object at {self._location}>"
107 
108     def append(self, item):
109         """Add the item to the end of a list"""
110         self._operations.append(_operation("Append", self._location, value=item))
111 
112     def prepend(self, item):
113         """Add the item to the start of a list"""
114         self._operations.append(_operation("Prepend", self._location, value=item))
115 
116     def insert(self, index, item):
117         """Add the item at the index of a list"""
118         self._operations.append(
119             _operation("Insert", self._location, value=item, index=index)
120         )
121 
122     def clear(self):
123         """Remove all items in a list"""
124         self._operations.append(_operation("Clear", self._location))
125 
126     def reverse(self):
127         """Reversal of the order of items in a list"""
128         self._operations.append(_operation("Reverse", self._location))
129 
130     def extend(self, item):
131         """Add all the items to the end of a list"""
132         if not isinstance(item, (list, tuple)):
133             raise TypeError(f"{item} should be a list or tuple")
134         self._operations.append(_operation("Extend", self._location, value=item))
135 
136     def remove(self, item):
137         """filter the item out of a list on the frontend"""
138         self._operations.append(_operation("Remove", self._location, value=item))
139 
140     def update(self, E=None, **F):
141         """Merge a dict or keyword arguments with another dictionary"""
142         value = E or {}
143         value.update(F)
144         self._operations.append(_operation("Merge", self._location, value=value))
145 
146     # pylint: disable=no-self-use
147     def sort(self):
148         raise KeyError(
149             "sort is reserved for future use, use brackets to access this key on your object"
150         )
151 
152     def to_plotly_json(self):
153         return {
154             "__dash_patch_update": "__dash_patch_update",
155             "operations": self._operations,
156         }
157
```
--- 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/dash/_patch.py b/dash/_patch.py
--- a/dash/_patch.py
+++ b/dash/_patch.py
@@ -36,18 +36,18 @@
     def __setstate__(self, state):
         vars(self).update(state)
 
-    def __getitem__(self, item):
+    def __getitem__(self, item) -> "Patch":
         validate_slice(item)
         return Patch(location=self._location + [item], parent=self)
 
-    def __getattr__(self, item):
+    def __getattr__(self, item) -> "Patch":
         if item == "tolist":
             # to_json fix
             raise AttributeError
         if item == "_location":
-            return self._location
+            return self._location  # type: ignore
         if item == "_operations":
-            return self._operations
+            return self._operations  # type: ignore
         return self.__getitem__(item)
 
     def __setattr__(self, key, value):
@@ -81,22 +81,32 @@
             self.extend(other)
         else:
             self._operations.append(_operation("Add", self._location, value=other))
+        if not self._location:
+            return self
         return _noop
 
     def __isub__(self, other):
         self._operations.append(_operation("Sub", self._location, value=other))
+        if not self._location:
+            return self
         return _noop
 
     def __imul__(self, other):
         self._operations.append(_operation("Mul", self._location, value=other))
+        if not self._location:
+            return self
         return _noop
 
     def __itruediv__(self, other):
         self._operations.append(_operation("Div", self._location, value=other))
+        if not self._location:
+            return self
         return _noop
 
     def __ior__(self, other):
         self.update(E=other)
+        if not self._location:
+            return self
         return _noop
 
     def __iter__(self):

{"golden_diff": "diff --git a/dash/_patch.py b/dash/_patch.py\n--- a/dash/_patch.py\n+++ b/dash/_patch.py\n@@ -36,18 +36,18 @@\n     def __setstate__(self, state):\n         vars(self).update(state)\n \n-    def __getitem__(self, item):\n+    def __getitem__(self, item) -> \"Patch\":\n         validate_slice(item)\n         return Patch(location=self._location + [item], parent=self)\n \n-    def __getattr__(self, item):\n+    def __getattr__(self, item) -> \"Patch\":\n         if item == \"tolist\":\n             # to_json fix\n             raise AttributeError\n         if item == \"_location\":\n-            return self._location\n+            return self._location  # type: ignore\n         if item == \"_operations\":\n-            return self._operations\n+            return self._operations  # type: ignore\n         return self.__getitem__(item)\n \n     def __setattr__(self, key, value):\n@@ -81,22 +81,32 @@\n             self.extend(other)\n         else:\n             self._operations.append(_operation(\"Add\", self._location, value=other))\n+        if not self._location:\n+            return self\n         return _noop\n \n     def __isub__(self, other):\n         self._operations.append(_operation(\"Sub\", self._location, value=other))\n+        if not self._location:\n+            return self\n         return _noop\n \n     def __imul__(self, other):\n         self._operations.append(_operation(\"Mul\", self._location, value=other))\n+        if not self._location:\n+            return self\n         return _noop\n \n     def __itruediv__(self, other):\n         self._operations.append(_operation(\"Div\", self._location, value=other))\n+        if not self._location:\n+            return self\n         return _noop\n \n     def __ior__(self, other):\n         self.update(E=other)\n+        if not self._location:\n+            return self\n         return _noop\n \n     def __iter__(self):\n", "issue": "[BUG] Patch += operation not working on the patch object.\nIf you have a patch object for a number prop and try to do `patched += 1`,  the callback will fail with an error, `returned non serializable object`.\r\n\r\nExample:\r\n```\r\napp = Dash()\r\napp.layout = [dcc.Store(data=0, store=\"store\"), html.Button(\"click\", id=\"click\")]\r\n@app.callback(Output(\"store\", \"data\"), Input(\"click\", \"n_clicks\"))\r\ndef on_click(_):\r\n    patched = Patch()\r\n    patched += 1\r\n    return patched\r\n```\r\n\r\nClicking on the button result in the error, it should instead update the store data prop to +1.\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 __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"}], "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) -> \"Patch\":\n        validate_slice(item)\n        return Patch(location=self._location + [item], parent=self)\n\n    def __getattr__(self, item) -> \"Patch\":\n        if item == \"tolist\":\n            # to_json fix\n            raise AttributeError\n        if item == \"_location\":\n            return self._location  # type: ignore\n        if item == \"_operations\":\n            return self._operations  # type: ignore\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        if not self._location:\n            return self\n        return _noop\n\n    def __isub__(self, other):\n        self._operations.append(_operation(\"Sub\", self._location, value=other))\n        if not self._location:\n            return self\n        return _noop\n\n    def __imul__(self, other):\n        self._operations.append(_operation(\"Mul\", self._location, value=other))\n        if not self._location:\n            return self\n        return _noop\n\n    def __itruediv__(self, other):\n        self._operations.append(_operation(\"Div\", self._location, value=other))\n        if not self._location:\n            return self\n        return _noop\n\n    def __ior__(self, other):\n        self.update(E=other)\n        if not self._location:\n            return self\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"}]}