mouse in pygame

 pygame.mouse.get_pos()
    get the mouse cursor position
    get_pos() -> (x, y)

    Returns the x and y position of the mouse cursor. 
    The position is relative to the top-left corner of the display. 
    The cursor position can be located outside of the display window,
    but is always constrained to the screen.

import math

def rotate(self):
    mouse_x, mouse_y = pygame.mouse.get_pos()
    rel_x, rel_y = mouse_x - self.x, mouse_y - self.y
    angle = (180 / math.pi) * -math.atan2(rel_y, rel_x)
    self.image = pygame.transform.rotate(self.original_image, int(angle))
    self.rect = self.image.get_rect(center=self.position)