<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def plot_joint_sfs_scaled(*args, **kwargs):
 """Plot a scaled joint site frequency spectrum. Parameters s : array_like, int, shape (n_chromosomes_pop1, n_chromosomes_pop2) Joint site frequency spectrum. ax : axes, optional Axes on which to draw. If not provided, a new figure will be created. imshow_kwargs : dict-like Additional keyword arguments, passed through to ax.imshow(). Returns ------- ax : axes The axes on which the plot was drawn. """

    imshow_kwargs = kwargs.get('imshow_kwargs', dict())
    imshow_kwargs.setdefault('norm', None)
    kwargs['imshow_kwargs'] = imshow_kwargs
    ax = plot_joint_sfs(*args, **kwargs)
    return ax