Add a `plot_theme` or similar function to complement `set_theme`

[mwaskom]

Like axes_style/set_style, this should report all of the parameters currently set in the theme and work as a context manager.

A little trickier because set() accepts arbitrary rcParams and the other theming functions don't.

Also needs a good name.

[CatNofishing]

Good idea, I'm looking forward to this feature. Also you can use with sns.axes_style("white"), sns.color_palette("pastel") To achieve this function，but it's obviously not convenient and it's not perfect。so please consider achieve this function: with sns.plot_theme(style='white',context='talk',palette='deep',rc=None)

[mwaskom]

This is easy enough to accomplish by stacking context managers:

with sns.axes_style("whitegrid"), sns.color_palette("Set2"):
    sns.boxplot(tips, x="total_bill", y="time", hue="sex")

Not convinced we need an additional function here.