I would re-arrange the psudo-code of Yaroslav a bit to include the
limit on the number of windows that can be made.  It also deals with
the case where switching and splitting are both off, and there is more
than one window, the user may want the execution buffer to be
displayed in one of the other windows.

Consider the case where switching is off, splitting is on, there are 2
windows neither of which are showing *Python*, and
py-max-split-windows = 2 (which I think is equivalent to splitting
being turned off).  What we want is this case is to put *Python* in the
window that our code is not in.  This generalizes to more than 2 windows 
directly by selecting the least recently used window.

(I wrote the psudo-code like python because I assume everyone
interested in this mode can read python. )


if py-manage-buffers-on-execute-p:
    # we want to make sure the user can see the output
    if *Python* buffer is visible:
        # we can already see *Python*, thus we are done    
        p_win = window *Python* is in
        pass
    else:
        # we need to try and make *Python* visible
        if py-split-windows-on-execute-p and count-windows < py-max-split-windows:
            # we can make a new window
            do the split and put *Python* in the new window
            p_win = new window
        else:
            if count-windows > 1:
                seleect some other window and put *Python* in it
                p_win = window *Python* was put in
            else:
                # this is the only branch where *Python* is not visible at the end
                p_win = None
                do nothing
                
    if py-switch-buffers-on-execute-p:
        if p_win:
            switch focus to p_win
        else:
            # this is the only branch that replaces the code window with the output
            switch the buffer displayed in the current window, replacing the code
else:
    # DO NOTHING
    pass

To deal with the use case where the user wants to always replace
the code window with the output (with what I think is a reasonable
exception of *Python* being already visible, in which case it behaves
like switching is turned on and splitting is turned off), we need to
add another flag.  If this flag (py-replace-code-on-execute-p) is set, 
the values of the split and switch flag are irrelevant.  

This logic is not in the lisp yet.


if py-manage-buffers-on-execute-p:
    # we want to make sure the user can see the output
    if *Python* buffer is visible:
        # we can already see *Python*, thus we are done    
        p_win = window *Python* is in
        pass
    else:
        if py-replace-code-on-execute-p:
            p_win = None
        # we need to try and make *Python* visible
        elif py-split-windows-on-execute-p and count-windows < py-max-split-windows:
            # we can make a new window
            do the split and put *Python* in the new window
            p_win = new window
        else:
            if count-windows > 1:
                seleect some other window and put *Python* in it
                p_win = window *Python* was put in
            else:
                # this is the only branch where *Python* is not visible at the end
                p_win = None
                do nothing
                
    if py-switch-buffers-on-execute-p or py-replace-code-on-execute-p:
        if p_win:
            switch focus to p_win
        else:
            # this is the only branch that replaces the code window with the output
            switch the buffer displayed in the current window, replacing the code
else:
    # DO NOTHING
    pass