code: def plot_parallel(
      ax,
      colornd,
      colord,
      shadend,
      diverging_mask,
      posterior,
      textsize,
      var_names,
      legend,
      figsize,
      backend_kwargs,
      backend_config,  # pylint: disable=unused-argument
      show,
  ):
      """Matplotlib parallel plot."""
      if backend_kwargs is None:
          backend_kwargs = {}
  
      backend_kwargs = {
          **backend_kwarg_defaults(),
          **backend_kwargs,
      }
  
      figsize, _, _, xt_labelsize, _, _ = _scale_fig_size(
          figsize, textsize, 1, 1
      )
      backend_kwargs.setdefault("figsize", figsize)
      backend_kwargs["squeeze"] = True
      if ax is None:
          _, ax = create_axes_grid(1, backend_kwargs=backend_kwargs)
  
      ax.plot(
          posterior[:, ~diverging_mask], color=colornd, alpha=shadend
      )
  
      if np.any(diverging_mask):
          ax.plot(posterior[:, diverging_mask], color=colord, lw=1)
  
      ax.tick_params(labelsize=textsize)
      ax.set_xticks(range(len(var_names)))
      ax.set_xticklabels(var_names)
  
      if legend:
          ax.plot([], color=colornd, label="non-divergent")
          if np.any(diverging_mask):
              ax.plot([], color=colord, label="divergent")
          ax.legend(fontsize=xt_labelsize)
  
      if backend_show(show):
          plt.show()
  
      return ax
  
imports: import matplotlib.pyplot
  import numpy
  from ...plot_utils import _scale_fig_size
  from .None import backend_kwarg_defaults, backend_show, create_axes_grid
label_desc: Use image node_id 1 for calling a global function with example usage: plot_parallel(ax, colornd, colord, shadend, diverging_mask, posterior, textsize, var_names, legend, figsize, backend_kwargs, backend_config, show) and returns: ax