We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Scrolling containers should be focusable by default
`ScrollHorizontal` and `ScrollVertical` should have `can_focus=True`.

Check this doesn't break any of the example apps.

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `src/textual/containers.py`
Content:
```
1 """
2 Container widgets for quick styling.
3 
4 """
5 
6 
7 from .widget import Widget
8 
9 
10 class Container(Widget):
11     """Simple container widget, with vertical layout."""
12 
13     DEFAULT_CSS = """
14     Container {
15         height: 1fr;
16         layout: vertical;
17         overflow: auto;
18     }
19     """
20 
21 
22 class Vertical(Widget):
23     """A container which arranges children vertically."""
24 
25     DEFAULT_CSS = """
26     Vertical {
27         width: 1fr;
28         layout: vertical;
29         overflow: hidden hidden;
30     }
31     """
32 
33 
34 class VerticalScroll(Widget):
35     """A container which arranges children vertically, with an automatic vertical scrollbar."""
36 
37     DEFAULT_CSS = """
38     VerticalScroll {
39         width: 1fr;
40         layout: vertical;
41         overflow-y: auto;
42     }
43     """
44 
45 
46 class Horizontal(Widget):
47     """A container which arranges children horizontally."""
48 
49     DEFAULT_CSS = """
50     Horizontal {
51         height: 1fr;
52         layout: horizontal;
53         overflow: hidden hidden;
54     }
55     """
56 
57 
58 class HorizontalScroll(Widget):
59     """A container which arranges children horizontally, with an automatic horizontal scrollbar."""
60 
61     DEFAULT_CSS = """
62     HorizontalScroll {
63         height: 1fr;
64         layout: horizontal;
65         overflow-x: auto;
66     }
67     """
68 
69 
70 class Center(Widget):
71     """A container which centers children horizontally."""
72 
73     DEFAULT_CSS = """
74     Center {
75         align-horizontal: center;
76         height: auto;
77         width: 1fr;
78     }
79     """
80 
81 
82 class Middle(Widget):
83     """A container which aligns children vertically in the middle."""
84 
85     DEFAULT_CSS = """
86     Middle {
87         align-vertical: middle;
88         width: auto;
89         height: 1fr;
90     }
91     """
92 
93 
94 class Grid(Widget):
95     """A container with grid alignment."""
96 
97     DEFAULT_CSS = """
98     Grid {
99         height: 1fr;
100         layout: grid;
101     }
102     """
103 
104 
105 class Content(Widget, can_focus=True, can_focus_children=False):
106     """A container for content such as text."""
107 
108     DEFAULT_CSS = """
109     VerticalScroll {
110         height: 1fr;
111         layout: vertical;
112         overflow-y: auto;
113     }
114     """
115
```
--- 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/src/textual/containers.py b/src/textual/containers.py
--- a/src/textual/containers.py
+++ b/src/textual/containers.py
@@ -31,7 +31,7 @@
     """
 
 
-class VerticalScroll(Widget):
+class VerticalScroll(Widget, can_focus=True):
     """A container which arranges children vertically, with an automatic vertical scrollbar."""
 
     DEFAULT_CSS = """
@@ -55,7 +55,7 @@
     """
 
 
-class HorizontalScroll(Widget):
+class HorizontalScroll(Widget, can_focus=True):
     """A container which arranges children horizontally, with an automatic horizontal scrollbar."""
 
     DEFAULT_CSS = """

{"golden_diff": "diff --git a/src/textual/containers.py b/src/textual/containers.py\n--- a/src/textual/containers.py\n+++ b/src/textual/containers.py\n@@ -31,7 +31,7 @@\n     \"\"\"\n \n \n-class VerticalScroll(Widget):\n+class VerticalScroll(Widget, can_focus=True):\n     \"\"\"A container which arranges children vertically, with an automatic vertical scrollbar.\"\"\"\n \n     DEFAULT_CSS = \"\"\"\n@@ -55,7 +55,7 @@\n     \"\"\"\n \n \n-class HorizontalScroll(Widget):\n+class HorizontalScroll(Widget, can_focus=True):\n     \"\"\"A container which arranges children horizontally, with an automatic horizontal scrollbar.\"\"\"\n \n     DEFAULT_CSS = \"\"\"\n", "issue": "Scrolling containers should be focusable by default\n`ScrollHorizontal` and `ScrollVertical` should have `can_focus=True`.\n\nCheck this doesn't break any of the example apps.\n", "before_files": [{"content": "\"\"\"\nContainer widgets for quick styling.\n\n\"\"\"\n\n\nfrom .widget import Widget\n\n\nclass Container(Widget):\n    \"\"\"Simple container widget, with vertical layout.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Container {\n        height: 1fr;\n        layout: vertical;\n        overflow: auto;\n    }\n    \"\"\"\n\n\nclass Vertical(Widget):\n    \"\"\"A container which arranges children vertically.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Vertical {\n        width: 1fr;\n        layout: vertical;\n        overflow: hidden hidden;\n    }\n    \"\"\"\n\n\nclass VerticalScroll(Widget):\n    \"\"\"A container which arranges children vertically, with an automatic vertical scrollbar.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    VerticalScroll {\n        width: 1fr;\n        layout: vertical;\n        overflow-y: auto;\n    }\n    \"\"\"\n\n\nclass Horizontal(Widget):\n    \"\"\"A container which arranges children horizontally.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Horizontal {\n        height: 1fr;\n        layout: horizontal;\n        overflow: hidden hidden;\n    }\n    \"\"\"\n\n\nclass HorizontalScroll(Widget):\n    \"\"\"A container which arranges children horizontally, with an automatic horizontal scrollbar.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    HorizontalScroll {\n        height: 1fr;\n        layout: horizontal;\n        overflow-x: auto;\n    }\n    \"\"\"\n\n\nclass Center(Widget):\n    \"\"\"A container which centers children horizontally.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Center {\n        align-horizontal: center;\n        height: auto;\n        width: 1fr;\n    }\n    \"\"\"\n\n\nclass Middle(Widget):\n    \"\"\"A container which aligns children vertically in the middle.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Middle {\n        align-vertical: middle;\n        width: auto;\n        height: 1fr;\n    }\n    \"\"\"\n\n\nclass Grid(Widget):\n    \"\"\"A container with grid alignment.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Grid {\n        height: 1fr;\n        layout: grid;\n    }\n    \"\"\"\n\n\nclass Content(Widget, can_focus=True, can_focus_children=False):\n    \"\"\"A container for content such as text.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    VerticalScroll {\n        height: 1fr;\n        layout: vertical;\n        overflow-y: auto;\n    }\n    \"\"\"\n", "path": "src/textual/containers.py"}], "after_files": [{"content": "\"\"\"\nContainer widgets for quick styling.\n\n\"\"\"\n\n\nfrom .widget import Widget\n\n\nclass Container(Widget):\n    \"\"\"Simple container widget, with vertical layout.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Container {\n        height: 1fr;\n        layout: vertical;\n        overflow: auto;\n    }\n    \"\"\"\n\n\nclass Vertical(Widget):\n    \"\"\"A container which arranges children vertically.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Vertical {\n        width: 1fr;\n        layout: vertical;\n        overflow: hidden hidden;\n    }\n    \"\"\"\n\n\nclass VerticalScroll(Widget, can_focus=True):\n    \"\"\"A container which arranges children vertically, with an automatic vertical scrollbar.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    VerticalScroll {\n        width: 1fr;\n        layout: vertical;\n        overflow-y: auto;\n    }\n    \"\"\"\n\n\nclass Horizontal(Widget):\n    \"\"\"A container which arranges children horizontally.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Horizontal {\n        height: 1fr;\n        layout: horizontal;\n        overflow: hidden hidden;\n    }\n    \"\"\"\n\n\nclass HorizontalScroll(Widget, can_focus=True):\n    \"\"\"A container which arranges children horizontally, with an automatic horizontal scrollbar.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    HorizontalScroll {\n        height: 1fr;\n        layout: horizontal;\n        overflow-x: auto;\n    }\n    \"\"\"\n\n\nclass Center(Widget):\n    \"\"\"A container which centers children horizontally.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Center {\n        align-horizontal: center;\n        height: auto;\n        width: 1fr;\n    }\n    \"\"\"\n\n\nclass Middle(Widget):\n    \"\"\"A container which aligns children vertically in the middle.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Middle {\n        align-vertical: middle;\n        width: auto;\n        height: 1fr;\n    }\n    \"\"\"\n\n\nclass Grid(Widget):\n    \"\"\"A container with grid alignment.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    Grid {\n        height: 1fr;\n        layout: grid;\n    }\n    \"\"\"\n\n\nclass Content(Widget, can_focus=True, can_focus_children=False):\n    \"\"\"A container for content such as text.\"\"\"\n\n    DEFAULT_CSS = \"\"\"\n    VerticalScroll {\n        height: 1fr;\n        layout: vertical;\n        overflow-y: auto;\n    }\n    \"\"\"\n", "path": "src/textual/containers.py"}]}