writing in to excel sheet with label

Dear all,

I am reading data from Serial port. data are in format below. Below code are seprating the data. I wanna know how can write it in excel sheet with time and date/mode/ dir/ actual postion as header and values which are CSV under paricular header


----------
time and date: 23-3-13 3:14:23
mode:1
dir:fw
actual pos:30
desired pos:28
------

import serial
import csv
import os
import time


def main():
    pass

if __name__ == '__main__':
    main()
    COUNT=0
    while(COUNT<=2):
      ser=serial.Serial()
      ser.port=12
      ser.baudrate=9600
      ser.open()
      str=ser.read(150)
      val=str.split(":")
      print "value is",val
      lines=str.split("\r\n")
      ser.close()
      COUNT=COUNT+1
    for lines in lines[:-1]:
            parts=lines.split(":")
            foo=open("new.txt","a+");
            foo.write("%s," % ":".join(parts[1:]))
            print parts[1:]
            foo.write("\n")
            foo.close()