Python如何判断直线和矩形是否相交？

"""
A(ax,ay),B(px,py)为两个点 （x1,y1）,(x2,y2)为矩形的左上角和右下角坐标 ,判断A，B两点是否和矩形相交 
"""
def Judge(ax, ay, px, py, x1, y1, x2, y2):
 #转换为真除法
 ax, ay, px, py = float(ax), float(ay), float(px), float(py)
 x1, y1, x2, y2 = float(x1), float(y1), float(x2), float(y2)
 #判断矩形上边线和两点直线相交的点
 sx = (y1 - ay) * (px - ax) / (py - ay) + ax
 if sx >= x1 and sx <= x2:
  return True
 #判断矩形下边线和两点直线相交的点
 xx = (y1 - ay) * (px - ax) / (py - ay) + ax
 if sx >= x1 and sx <= x2:
  return True
 #判断矩形左边线和两点直线相交的点
 zy = (y2 - ay) * (x2 - ax) / (px - ax) + ay
 if zy >= y1 and zy <= y2:
  return True
 #判断矩形右边线和两点直线相交的点
 yy = (y2 - ay) * (x2 - ax) / (px - ax) + ay
 if yy <= y1 and yy >= y2:
  return True
 return False
ax = raw_input()
ay = input()
px = input()
py = input()
x1 = input()
y1 = input()
x2 = input()
y2 = input()
print Judge(ax, ay, px, py, x1, y1, x2, y2)