Cleanup unused imports and variables in backends (matplotlib#22502)

Author: oscargus

lib/matplotlib/backends/backend_agg.py

@@ -29,11 +29,9 @@
 from math import radians, cos, sin
 
 import numpy as np
-from PIL import Image
 
 import matplotlib as mpl
 from matplotlib import _api, cbook
-from matplotlib import colors as mcolors
 from matplotlib.backend_bases import (
     _Backend, FigureCanvasBase, FigureManagerBase, RendererBase)
 from matplotlib.font_manager import findfont, get_font
@@ -152,7 +150,7 @@ def draw_path(self, gc, path, transform, rgbFace=None):
                 p.simplify_threshold = path.simplify_threshold
                 try:
                     self._renderer.draw_path(gc, p, transform, rgbFace)
-                except OverflowError as err:
+                except OverflowError:
                     msg = (
                         "Exceeded cell block limit in Agg.\n\n"
                         "Please reduce the value of "
@@ -167,7 +165,7 @@ def draw_path(self, gc, path, transform, rgbFace=None):
         else:
             try:
                 self._renderer.draw_path(gc, path, transform, rgbFace)
-            except OverflowError as err:
+            except OverflowError:
                 cant_chunk = ''
                 if rgbFace is not None:
                     cant_chunk += "- can not split filled path\n"

lib/matplotlib/backends/backend_gtk3.py

@@ -8,7 +8,6 @@
 from matplotlib import _api, backend_tools, cbook
 from matplotlib.backend_bases import FigureCanvasBase, ToolContainerBase
 from matplotlib.backend_tools import Cursors
-from matplotlib.figure import Figure
 
 try:
     import gi
@@ -27,9 +26,10 @@
 from gi.repository import Gio, GLib, GObject, Gtk, Gdk
 from . import _backend_gtk
 from ._backend_gtk import (
-    backend_version, _BackendGTK, _FigureManagerGTK, _NavigationToolbar2GTK,
+    _BackendGTK, _FigureManagerGTK, _NavigationToolbar2GTK,
     TimerGTK as TimerGTK3,
 )
+from ._backend_gtk import backend_version  # noqa: F401 # pylint: disable=W0611
 
 
 _log = logging.getLogger(__name__)
@@ -50,7 +50,7 @@ def cursord(self):
                 Cursors.SELECT_REGION: new_cursor("crosshair"),
                 Cursors.WAIT:          new_cursor("wait"),
             }
-        except TypeError as exc:
+        except TypeError:
             return {}
 
     icon_filename = _api.deprecated("3.6", obj_type="")(property(

lib/matplotlib/backends/backend_gtk4.py

@@ -1,7 +1,6 @@
 import functools
 import io
 import os
-from pathlib import Path
 
 import matplotlib as mpl
 from matplotlib import _api, backend_tools, cbook
@@ -24,9 +23,10 @@
 from gi.repository import Gio, GLib, GObject, Gtk, Gdk, GdkPixbuf
 from . import _backend_gtk
 from ._backend_gtk import (
-    backend_version, _BackendGTK, _FigureManagerGTK, _NavigationToolbar2GTK,
+    _BackendGTK, _FigureManagerGTK, _NavigationToolbar2GTK,
     TimerGTK as TimerGTK4,
 )
+from .backend_gtk import backend_version  # noqa: F401 # pylint: disable=W0611
 
 
 class FigureCanvasGTK4(Gtk.DrawingArea, FigureCanvasBase):

lib/matplotlib/backends/backend_macosx.py

@@ -1,8 +1,8 @@
 import matplotlib as mpl
 from matplotlib import cbook
 from matplotlib._pylab_helpers import Gcf
-from matplotlib.backends import _macosx
-from matplotlib.backends.backend_agg import FigureCanvasAgg
+from . import _macosx
+from .backend_agg import FigureCanvasAgg
 from matplotlib.backend_bases import (
     _Backend, FigureCanvasBase, FigureManagerBase, NavigationToolbar2,
     TimerBase)

lib/matplotlib/backends/backend_mixed.py

@@ -1,7 +1,7 @@
 import numpy as np
 
 from matplotlib import cbook
-from matplotlib.backends.backend_agg import RendererAgg
+from .backend_agg import RendererAgg
 from matplotlib._tight_bbox import process_figure_for_rasterizing
 
 

lib/matplotlib/backends/backend_nbagg.py

@@ -20,10 +20,10 @@
 from matplotlib import is_interactive
 from matplotlib._pylab_helpers import Gcf
 from matplotlib.backend_bases import _Backend, NavigationToolbar2
-from matplotlib.backends.backend_webagg_core import (
-    FigureCanvasWebAggCore, FigureManagerWebAgg, NavigationToolbar2WebAgg,
-    TimerTornado, TimerAsyncio
-)
+from .backend_webagg_core import (
+    FigureCanvasWebAggCore, FigureManagerWebAgg, NavigationToolbar2WebAgg)
+from .backend_webagg_core import (  # noqa: F401 # pylint: disable=W0611
+    TimerTornado, TimerAsyncio)
 
 
 def connection_info():

lib/matplotlib/backends/backend_pgf.py

@@ -18,8 +18,7 @@
 import matplotlib as mpl
 from matplotlib import _api, cbook, font_manager as fm
 from matplotlib.backend_bases import (
-    _Backend, FigureCanvasBase, FigureManagerBase, GraphicsContextBase,
-    RendererBase
+    _Backend, FigureCanvasBase, FigureManagerBase, RendererBase
 )
 from matplotlib.backends.backend_mixed import MixedModeRenderer
 from matplotlib.backends.backend_pdf import (

lib/matplotlib/backends/backend_qt.py

@@ -405,8 +405,7 @@ def start_event_loop(self, timeout=0):
             raise RuntimeError("Event loop already running")
         self._event_loop = event_loop = QtCore.QEventLoop()
         if timeout > 0:
-            timer = QtCore.QTimer.singleShot(int(timeout * 1000),
-                                             event_loop.quit)
+            _ = QtCore.QTimer.singleShot(int(timeout * 1000), event_loop.quit)
 
         with _maybe_allow_interrupt(event_loop):
             qt_compat._exec(event_loop)

lib/matplotlib/backends/backend_qt5agg.py

@@ -2,8 +2,9 @@
 Render to qt from agg
 """
 
-from .backend_qtagg import (
-    _BackendQTAgg, FigureCanvasQTAgg, FigureManagerQT, NavigationToolbar2QT,
+from .backend_qtagg import _BackendQTAgg
+from .backend_qtagg import (  # noqa: F401 # pylint: disable=W0611
+    FigureCanvasQTAgg, FigureManagerQT, NavigationToolbar2QT,
     backend_version,  FigureCanvasAgg,  FigureCanvasQT
 )
 

lib/matplotlib/backends/backend_qt5cairo.py

@@ -1,5 +1,6 @@
-from .backend_qtcairo import (
-    _BackendQTCairo, FigureCanvasQTCairo, FigureCanvasCairo, FigureCanvasQT)
+from .backend_qtcairo import _BackendQTCairo
+from .backend_qtcairo import (  # noqa: F401 # pylint: disable=W0611
+    FigureCanvasQTCairo, FigureCanvasCairo, FigureCanvasQT)
 
 
 @_BackendQTCairo.export