class_docstr: Utility renderer using Matplotlib to render a grid of plots over the same (x, y) range.
  
  Args:
      nrows (int, optional): Number of rows of plots, default ``1``.
      ncols (int, optional): Number of columns of plots, default ``1``.
      figsize (tuple(float, float), optional): Figure size in inches, default ``(9, 9)``.
      show_frame (bool, optional): Whether to show frame and axes ticks, default ``True``.
      backend (str, optional): Matplotlib backend to use or ``None`` for default backend.
          Default ``None``.
      gridspec_kw (dict, optional): Gridspec keyword arguments to pass to ``plt.subplots``,
          default None.
docstr: Plot masked out grid points as circles on a single Axes.
  
  Args:
      x (array-like of shape (ny, nx) or (nx,)): The x-coordinates of the grid points.
      y (array-like of shape (ny, nx) or (ny,)): The y-coordinates of the grid points.
      z (masked array of shape (ny, nx): z-values.
      ax (int or Matplotlib Axes, optional): Which Axes to plot on, default ``0``.
      color (str, optional): Circle color, default ``"black"``.
code: def mask(
      self,
      x: ArrayLike,
      y: ArrayLike,
      z: ArrayLike | np.ma.MaskedArray[Any, Any],
      ax: Axes | int = 0,
      color: str = "black",
  ) -> None:
      """Plot masked out grid points as circles on a single Axes.
  
      Args:
          x (array-like of shape (ny, nx) or (nx,)): The x-coordinates of the grid points.
          y (array-like of shape (ny, nx) or (ny,)): The y-coordinates of the grid points.
          z (masked array of shape (ny, nx): z-values.
          ax (int or Matplotlib Axes, optional): Which Axes to plot on, default ``0``.
          color (str, optional): Circle color, default ``"black"``.
      """
      mask = np.ma.getmask(z)  # type: ignore[no-untyped-call]
      if mask is np.ma.nomask:
          return
      ax = self._get_ax(ax)
      x, y = self._grid_as_2d(x, y)
      ax.plot(x[mask], y[mask], "o", c=color)
  
imports: from __future__ import annotations
  from collections.abc import Sequence
  import io
  from typing import TYPE_CHECKING, Any, cast
  import matplotlib.collections
  import matplotlib.pyplot
  import numpy
  from contourpy import FillType, LineType
  from contourpy.convert import convert_filled, convert_lines
  from contourpy.enum_util import as_fill_type, as_line_type
  from contourpy.util.mpl_util import filled_to_mpl_paths, lines_to_mpl_paths
  from contourpy.util.renderer import Renderer
label_desc: Use image node_id 8 for calling the MplRenderer obj's underlying member method code with example usage: obj.mask(x, y, z, ax, color) without return types