Show `xs` (inputs), `ys` (targets) and `zs` (predictions) on a figure of `figsize`.

def show_xyzs(self, xs, ys, zs, imgsize:int=4, figsize:Optional[Tuple[int,int]]=None, **kwargs):
        "Show `xs` (inputs), `ys` (targets) and `zs` (predictions) on a figure of `figsize`."
        title = 'Input / Prediction / Target'
        axs = subplots(len(xs), 3, imgsize=imgsize, figsize=figsize, title=title, weight='bold', size=14)
        for i,(x,y,z) in enumerate(zip(xs,ys,zs)):
            x.show(ax=axs[i,0], **kwargs)
            y.show(ax=axs[i,2], **kwargs)
            z.show(ax=axs[i,1], **kwargs)