import curses 

screen = curses.initscr() 
#curses.noecho() 
curses.curs_set(0) 
screen.keypad(1) 
curses.mousemask(1)

screen.addstr("This is a Sample Curses Script\n\n") 

while True:
    event = screen.getch() 
    if event == ord("q"): break 
    if event == curses.KEY_MOUSE:
        _, mx, my, _, _ = curses.getmouse()
        y, x = screen.getyx()
        screen.addstr(y, x, screen.instr(my, mx, 5))

curses.endwin()

You should read the docs more carefully, it's all in there :-)

I know this is a pretty old question and the OP might not need it anymore, but I'm leaving it here for anyone who stumbles upon this question after hours of googling and head scratching:

import curses

def main(win:curses.window):
    win.clear()
    win.nodelay(True)
    curses.mousemask(curses.REPORT_MOUSE_POSITION)
    print('\033[?1003h') # enable mouse tracking with the XTERM API
    # https://invisible-island.net/xterm/ctlseqs/ctlseqs.html#h2-Mouse-Tracking

    while True:
        ch=win.getch()
        if ch==curses.KEY_MOUSE:
            win.clear()
            win.addstr(0,0,str(curses.getmouse()[1:3]))
            win.refresh()

curses.wrapper(main)

The most important line here is the print('\033[?1003h'), which enables the mouse position reporting to the program, while the mousemask enables curses to interpret the input from the terminal. Note that the print must appear after the mousemask() is called.

Tested on macOS 10.14.6 with iTerm2. There is no tweak to the terminfo.

I got it to work by changing my $TERM env var / terminfo. On Ubuntu it worked by simply setting TERM=screen-256color, but on OSX I had to edit a terminfo file, using the instructions here:

Which $TERM to use to have both 256 colors and mouse move events in python curses?

but for me the format was different so I added the line:

XM=\E[?1003%?%p1%{1}%=%th%el%;,

To test it, I used this Python code (note screen.keypad(1) is very necessary, otherwise mouse events cause getch to return escape key codes).

import curses

screen = curses.initscr()
screen.keypad(1)
curses.curs_set(0)
curses.mousemask(curses.ALL_MOUSE_EVENTS | curses.REPORT_MOUSE_POSITION)
curses.flushinp()
curses.noecho()
screen.clear()

while True:
    key = screen.getch()
    screen.clear()
    screen.addstr(0, 0, 'key: {}'.format(key))
    if key == curses.KEY_MOUSE:
        _, x, y, _, button = curses.getmouse()
        screen.addstr(1, 0, 'x, y, button = {}, {}, {}'.format(x, y, button))
    elif key == 27:
        break

curses.endwin()
curses.flushinp()