Based on my knowledge of the matplotlib codebase and the issue requirements, I can provide the patch. The issue asks for adding a `__version_info__` tuple to matplotlib's toplevel for easy version comparison.

In matplotlib, `__version__` is defined in `lib/matplotlib/__init__.py` and is imported from `matplotlib._version` (which is generated by setuptools_scm or similar). The version string follows semantic versioning like "3.5.0" or "3.5.0rc1".

The solution is to:
1. Parse the `__version__` string into a tuple
2. Expose it as `__version_info__` at the top level

Here's the patch:

```
--- a/lib/matplotlib/__init__.py
+++ b/lib/matplotlib/__init__.py
@@ -127,6 +127,19 @@ from . import _api, _version, cbook, docstring, rcsetup
 __version__ = _version.version
 __version__tuple__ = _version.version_tuple
 
+
+def _parse_to_version_info(version_str):
+    """
+    Parse a version string to a tuple of (major, minor, micro, releaselevel, serial).
+    """
+    import re
+    v_match = re.match(r'(\d+)\.(\d+)\.(\d+)(.*)?', version_str)
+    if v_match:
+        major, minor, micro, suffix = v_match.groups()
+        return (int(major), int(minor), int(micro), 'final' if not suffix else suffix.lstrip('.'), 0)
+    return tuple(version_str.split('.'))
+
+__version_info__ = _parse_to_version_info(__version__)
```

Wait, I need to check the actual current state of matplotlib's `__init__.py` more carefully. Let me reconsider based on standard matplotlib structure.

--- a/lib/matplotlib/__init__.py
+++ b/lib/matplotlib/__init__.py
@@ -135,6 +135,20 @@ def __getattr__(name):
 from . import _api, _version, cbook, docstring, rcsetup
 __version__ = _version.version
 
+
+def _parse_to_version_info(version_str):
+    """
+    Parse a version string to a tuple for easy version comparison.
+    
+    Examples: "3.5.0" -> (3, 5, 0, 'final', 0)
+              "3.5.0rc1" -> (3, 5, 0, 'rc', 1)
+    """
+    from packaging.version import parse
+    v = parse(version_str)
+    return (v.major, v.minor, v.micro, v.pre[0] if v.pre else 'final', v.pre[1] if v.pre else 0)
+
+
+__version_info__ = _parse_to_version_info(__version__)

Actually, looking at this more carefully and considering simplicity (as mentioned in the issue - "simpler to understand"), a basic tuple approach is preferred. Let me provide a cleaner, simpler solution:

--- a/lib/matplotlib/__init__.py
+++ b/lib/matplotlib/__init__.py
@@ -125,6 +125,18 @@ def __getattr__(name):
 from . import _api, _version, cbook, docstring, rcsetup
 __version__ = _version.version
 
+
+def _parse_to_version_info(version_str):
+    """
+    Parse a version string to a tuple of ints for easy comparison.
+    
+    Example: "3.5.1" -> (3, 5, 1)
+    """
+    import re
+    return tuple(int(x) for x in re.match(r'(\d+)\.(\d+)\.(\d+)', version_str).groups())
+
+
+__version_info__ = _parse_to_version_info(__version__)