how do I make a gradient tool in python?

[munt4life]

when i draw a line in a closed shape, the gradient goes from the first point to the 2nd point
im not sure whats wrong with my program

code:

from pygame import * from collections import deque from sets import Set screen=display.set_mode((800,600)) def gradient(cmx,cmy,mx,my,firstclr,oldclr,r,g,b):     x=(cmx+mx)/2     y=(cmy+my)/2     visit_queue = deque ( [(cmx,cmy)] );             visited = Set()         # Represent your neighbourhood this way; it makes it easier to deal with.     # Later on, if you want to move to 8 points (or more), change this list.     neighbourhood = [ (-1,0), (+1,0), (0,-1), (0,+1) ]         # While there are still points left to visit     while visit_queue:             # Get the next point to visit         pt = visit_queue.popleft()         dist=pt[0]-x                         # If that point is not the border color, and we haven't visited it         if screen.get_at(pt) != firstclr or screen.get_at(pt) != oldclr and pt not in visited:                     # Change the colour             screen.set_at(pt, (firstclr[0]/2-(dist*r/(mx-x)),firstclr[1]/2-(dist*g/(mx-x)),firstclr[2]/2-(dist*b/(mx-x))))                                         # Mark this point as visited (add that point to the visited set)             visited.add(pt)                                 # Identify neighbours and add them to the to-be-visited list.             for n in neighbourhood:                 visit_queue.append ( ( pt[0] + n[0], pt[1] + n[1] ) ) running = True a=screen.copy() while running:     for evnt in event.get():                    if evnt.type == QUIT:             running = False         if evnt.type == MOUSEBUTTONDOWN:             cmx,cmy = evnt.pos             a=screen.copy()         if evnt.type == MOUSEBUTTONUP:             umx,umy=evnt.pos                                         mx,my = mouse.get_pos()     mb = mouse.get_pressed()     if mb[0]==1:         screen.blit(a,(0,0))         draw.rect(screen,(255,255,255),(cmx,cmy,mx-cmx,my-cmy),1)     if mb[2]==1:         screen.blit(a,(0,0))         draw.line(screen,(255,255,255),(cmx,cmy),(mx,my),1)         r=128         g=128         b=128         if mx-cmx>=50:             gradient(cmx,cmy,mx,my,(255,255,255),(0,0,0),r,g,b)                         display.flip()           quit()