在Python 2.7中运行PHP脚本

Question

I am wondering how to execute a php code if a python statement is true.As an example I need to do something like this.I am using Python 2.7 because im sending an email using 2.7 libraries.This doesnt work,i've been writing on python for 2 days and i dont know much about it .It also gives me an error:

import subprocess
import os
a=input(" ")
if(a>0):
   subprocess.call(["php", "write.php"])

Traceback (most recent call last):
   File "D:\PROGRAMS\xamkpp\htdocs\proba.py", line 5, in <module>
     subprocess.call(["php", "write.php"])
   File "C:\Python27\lib\subprocess.py", line 522, in call
     return Popen(*popenargs, **kwargs).wait()
   File "C:\Python27\lib\subprocess.py", line 710, in __init__
     errread, errwrite)
   File "C:\Python27\lib\subprocess.py", line 958, in _execute_child
     startupinfo)
 WindowsError: [Error 2] The system cannot find the file specified