getAngle

# getAngle
from pymel.core import *
def getDist(a,b):
    s1t = getPiv(a)
    s2t = getPiv(b)
    dist = math.sqrt((s2t[0] - s1t[0])**2 + (s2t[1] - s1t[1])**2 + (s2t[2] - s1t[2])**2)
    return dist
def getAngle(a,b):
    l1 = spaceLocator()
    pc1 = pointConstraint(a,l1)
    l2 = spaceLocator()
    pc2 = pointConstraint(b,l2)
    ac = aimConstraint(l2,l1,aim = [0,1,0], u=[0,1,0])
    r1 = a.getRotation()
    r2 = l1.getRotation()
    x = r1[0]+r2[0]/2
    y = r1[1]+r2[1]/2
    z = r1[2]+r2[2]/2
    angle = x,y,z
    delete(l1,l2,pc1,pc2,ac)
    return angle
sl = selected()
a = getAngle(sl[0],sl[1])

rotate(sl[0], a)