Convert function

I have found a user defined function to convert the ip to long in Spark, but I need to write it in pyspark. I am new to both of them and I do not know how to do that. Could someone help? Here is the function:

val ipToLong = udf((ip: String) => {
          if (ip != null && ip != "" && ip.contains(".")) {
            val atoms: Array[Long] = ip.split("\\.").map(java.lang.Long.parseLong(_))
            val result: Long = (3 to 0 by -1).foldLeft(0L)(
              (result, position) => result | (atoms(3 - position) << position * 8))

            result & 0xFFFFFFFF
          } else {
            -1
          }
        })