docstr: Get the image as a `memoryview` to the renderer's buffer.
  
  `draw` must be called at least once before this function will work and
  to update the renderer for any subsequent changes to the Figure.
code: def buffer_rgba(self):
      """
      Get the image as a `memoryview` to the renderer's buffer.
  
      `draw` must be called at least once before this function will work and
      to update the renderer for any subsequent changes to the Figure.
      """
      return self.renderer.buffer_rgba()
  
imports: from contextlib import nullcontext
  from math import radians, cos, sin
  import numpy
  import matplotlib
  from matplotlib import _api, cbook
  from matplotlib.backend_bases import _Backend, FigureCanvasBase, FigureManagerBase, RendererBase
  from matplotlib.font_manager import fontManager, get_font
  from matplotlib.ft2font import LOAD_FORCE_AUTOHINT, LOAD_NO_HINTING, LOAD_DEFAULT, LOAD_NO_AUTOHINT
  from matplotlib.mathtext import MathTextParser
  from matplotlib.path import Path
  from matplotlib.transforms import Bbox, BboxBase
  from matplotlib.backends._backend_agg import RendererAgg
label_desc: Use image node_id 7 for calling the FigureCanvasAgg obj's underlying member method code with example usage: obj.buffer_rgba() and returns: self