matplotlib
diff --git a/‎lib/matplotlib/backend_bases.py‎
Lines changed: 1 addition & 2 deletions b/‎lib/matplotlib/backend_bases.py‎
Lines changed: 1 addition & 2 deletions
diff --git a/‎lib/matplotlib/backends/registry.py‎
Lines changed: 11 additions & 13 deletions b/‎lib/matplotlib/backends/registry.py‎
Lines changed: 11 additions & 13 deletions
@@ -2039,8 +2039,7 @@ def _switch_canvas_and_return_print_method(self, fmt, backend=None):
         if backend is not None:
             # Return a specific canvas class, if requested.
             from .backends.registry import backend_registry
-            canvas_class = (
-                backend_registry.load_backend_module(backend).FigureCanvas)
+            canvas_class = backend_registry.load_backend_module(backend).FigureCanvas
             if not hasattr(canvas_class, f"print_{fmt}"):
                 raise ValueError(
                     f"The {backend!r} backend does not support {fmt} output")
 
@@ -98,10 +98,10 @@ def _backend_module_name(self, backend):
         backend = backend.lower()
 
         # Check if have specific name to module mapping.
-        backend = self._name_to_module.get(backend) or backend
+        backend = self._name_to_module.get(backend, backend)
 
         return (backend[9:] if backend.startswith("module://")
-                else f"matplotlib.backends.backend_{backend.lower()}")
+                else f"matplotlib.backends.backend_{backend}")
 
     def _clear(self):
         # Clear all dynamically-added data, used for testing only.
@@ -136,7 +136,7 @@ def _read_entry_points(self):
         if sys.version_info >= (3, 10):
             entry_points = im.entry_points(group=group)
         else:
-            entry_points = im.entry_points().get(group, {})
+            entry_points = im.entry_points().get(group, ())
         entries = [(entry.name, entry.value) for entry in entry_points]
 
         # For backward compatibility, if matplotlib-inline and/or ipympl are installed
@@ -199,7 +199,7 @@ def backend_for_gui_framework(self, framework):
         """
         return self._GUI_FRAMEWORK_TO_BACKEND.get(framework.lower())
 
-    def is_valid_backend(self, backend: str) -> bool:
+    def is_valid_backend(self, backend):
         """
         Return True if the backend name is valid, False otherwise.
 
@@ -262,7 +262,7 @@ def list_all(self):
             Backend names.
         """
         self._ensure_entry_points_loaded()
-        return self.list_builtin() + list(self._backend_to_gui_framework.keys())
+        return [*self.list_builtin(), *self._backend_to_gui_framework]
 
     def list_builtin(self, filter_=None):
         """
@@ -286,19 +286,18 @@ def list_builtin(self, filter_=None):
             return [k for k, v in self._BUILTIN_BACKEND_TO_GUI_FRAMEWORK.items()
                     if v == "headless"]
 
-        return list(self._BUILTIN_BACKEND_TO_GUI_FRAMEWORK.keys())
+        return [*self._BUILTIN_BACKEND_TO_GUI_FRAMEWORK]
 
     def list_gui_frameworks(self):
         """
-        Return list of gui frameworks used by Matplotlib backends.
+        Return list of GUI frameworks used by Matplotlib backends.
 
         Returns
         -------
         list of str
             GUI framework names.
         """
-        return [k for k in self._GUI_FRAMEWORK_TO_BACKEND.keys()
-                if k != "headless"]
+        return [k for k in self._GUI_FRAMEWORK_TO_BACKEND if k != "headless"]
 
     def load_backend_module(self, backend):
         """
@@ -321,7 +320,7 @@ def resolve_backend(self, backend):
         """
         Return the backend and GUI framework for the specified backend name.
 
-        If the GUI framework is not yet known then it will be determine by loading the
+        If the GUI framework is not yet known then it will be determined by loading the
         backend module and checking the ``FigureCanvas.required_interactive_framework``
         attribute.
 
@@ -351,8 +350,7 @@ def resolve_backend(self, backend):
                self._backend_to_gui_framework.get(backend))
 
         # Is backend "module://something"?
-        if (gui is None and isinstance(backend, str) and
-                backend.startswith("module://")):
+        if gui is None and isinstance(backend, str) and backend.startswith("module://"):
             gui = "unknown"
 
         # Is backend a possible entry point?
@@ -389,7 +387,7 @@ def resolve_gui_or_backend(self, gui_or_backend):
 
         Returns
         -------
-        Tuple of backend (str) and GUI framework (str or None).
+        tuple of (str, str or None)
             A non-interactive backend returns None for its GUI framework rather than
             "headless".
         """