axs - iterable of mpl.axes.Axes
posn - string where the label is placed
type - string from {'a', 'A', 'i', 'I', '1'} (what other options are there?)
start - int to start labelling from
fstr - format string, the text added is fstr.format(char)
**kwargs - keyword arguments passed on to ax.text()
Suggested interface - the function name can be changed
pg.add_numbering(axs, posn="upper left", type='a', start=1, fstr="({})", **kwargs)
axs - iterable of mpl.axes.Axes posn - string where the label is placed type - string from {'a', 'A', 'i', 'I', '1'} (what other options are there?) start - int to start labelling from fstr - format string, the text added is fstr.format(char) **kwargs - keyword arguments passed on to ax.text()