CRV from Transform

# CRV from Transform
from pymel.core import*
import random as r
sl = selected()
for s in sl:
    p = str(s)
    ex = "vector $pos = <<"+p+".translateX,"+p+".translateY,"+p+".translateZ>>;"+"\n"
    ex += "string $curveName ="
    ex += "\""+p+"_MotionCrv\";"
    ex += "\n"
    ex += "if(frame == 2){"
    ex += "\n"
    ex += "int $objTest = `objExists $curveName`;"
    ex += "\n"
    ex += "if ($objTest == 1)"
    ex += "\n"
    ex += "{"+"\n"
    ex += "delete $curveName;"
    ex += "\n"
    ex += "}"+"\n"
    ex += "curve -p ($pos.x) ($pos.y) ($pos.z) -n $curveName;"
    ex += "\n"
    ex += "}"
    ex += "\n"
    ex += "if(frame >= 3)"
    ex += "\n"
    ex += "{"
    ex += "\n"
    ex += "curve -append -p ($pos.x) ($pos.y) ($pos.z) $curveName;"
    ex += "\n"
    ex += "}"+"\n"
    expression(s, s = ex, n = s+"_Crv_Expression")