something_image.py

import win32api
from win32api import GetSystemMetrics
import win32con
import pygame
import win32gui
import pyautogui

pygame.init()
screen = pygame.display.set_mode((GetSystemMetrics(0), GetSystemMetrics(1)), pygame.FULLSCREEN, pygame.NOFRAME) # For borderless, use pygame.NOFRAME
done = False
fuchsia = (255, 0, 128)  # Transparency color
dark_red = (139, 0, 0)

# Set window transparency color
hwnd = pygame.display.get_wm_info()["window"]
win32gui.SetWindowLong(hwnd, win32con.GWL_EXSTYLE,
                       win32gui.GetWindowLong(hwnd, win32con.GWL_EXSTYLE) | win32con.WS_EX_LAYERED)
win32gui.SetLayeredWindowAttributes(hwnd, win32api.RGB(*fuchsia), 0, win32con.LWA_COLORKEY)

#Some controls
block=0
block1=0

#You can render some text
white=(255,255,255)
blue=(0,0,255)
font = pygame.font.Font('freesansbold.ttf', 32) 
texto=font.render('press "z" to define one corner and again to define the rectangle, it will take a screenshot', True, white, blue)
while not done:

    keys= pygame.key.get_pressed()
    pygame.time.delay(50)

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            done = True

    #This controls the actions at starting and end point
    if block1==0:
        if keys[pygame.K_z]:
            if block==0:
                block=1
                n=win32gui.GetCursorPos()
            else:
                done=True
                break
            #this prevents double checks, can be handle also by using events
            block1=10

        else:
            m=win32gui.GetCursorPos()
    else:
        block1-=1        

    screen.fill(fuchsia)  # Transparent background
    #this will render some text
    screen.blit(texto,(0,0))
    #This will draw your rectangle
    if block==1:
        pygame.draw.line(screen,dark_red,(n[0],n[1]),(m[0],n[1]),1)
        pygame.draw.line(screen,dark_red,(n[0],m[1]),(m[0],m[1]),1)
        pygame.draw.line(screen,dark_red,(n[0],n[1]),(n[0],m[1]),1)
        pygame.draw.line(screen,dark_red,(m[0],n[1]),(m[0],m[1]),1)
        #    Drawing the independent lines is still a little faster than drawing a rectangle
        pygame.draw.rect(screen,dark_red,(min(n[0],m[0]),min(n[1],m[1]),abs(m[0]-n[0]),abs(m[1]-n[1])),1)
    pygame.display.update()    

pygame.display.quit()
pyautogui.screenshot(region=(min(n[0],m[0]),min(n[1],m[1]),abs(m[0]-n[0]),abs(m[1]-n[1])))