[Tutor] Attribute error?

[desiderata at softhome.net]

Hi,

This is my first time using python and I've got a problem appending to a
file... here's my short code:

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#!/usr/bin/python

uid = raw_input("Please enter your userID: ")
gid = raw_input("Please enter your gID: ")
f = open("file.txt","a")
f.append("\nYour userID is " + uid + " And your gID is " + gid)
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but when I input the values while executing it, it gives me an error:

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Traceback (most recent call last):
  File "./test2.py", line 6, in ?
      f.append("\nYour userID is " + uid + " And your gID is " + gid) 
      AttributeError: 'file' object has no attribute 'append'
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but I already used "a" for it to append.. I don't get it =( 


regards, 
Elijah