Is it possible to use output from raw_input() as a new file name?

Question

I'm wondering if it's possible to use the return from raw_input()to create a file name?

What I have so far:

import os
from Tkinter import Tk
from tkFileDialog import askopenfilename
Tk().withdraw()
ttnum=str(raw_input('Please enter ticket number: '))
ttnum
filename=askopenfilename()
abspath = os.path.abspath(filename) 
dname = os.path.dirname(abspath)    
os.chdir(dname)                     
f=open(filename)
contents=f.read()
file_len(filename)
file_scan(filename)

Portion of code that calls ttnum:

def file_len(filename):
#Count the number of line in the Text File
    f1 = open(("WiFi Logs report for tt " + ttnum,'w'))
    with open(filename) as f:
        for i, l in enumerate(f):
            pass     
    f1.write('Total number of lines in file: ' + str(i+1) + '\n' + '\n')
    f1.close()  

def file_scan(filename):
#List of issues to Scan For
    f1 = open(("WiFi Logs report for tt " + ttnum,'a'))

I can enter input no problem (in this case 12345), but once it hits the code, I get the following:

Traceback (most recent call last):
  File "M:\WiFi Log Scanner\WiFi_Log_Scanner.py", line 153, in <module>
    file_len(filename)
  File "M:\WiFi Log Scanner\WiFi_Log_Scanner.py", line 4, in file_len
    f1 = open(("WiFi Logs report for tt " + ttnum,'w'))
TypeError: coercing to Unicode: need string or buffer, tuple found

I thought that the str() at the start would ensure that it is, well, a string and not a tuple?

Any insight would be appreciated.

Thanks,

Joe

Answer 1

Remove a layer of parentheses from open(("WiFi Logs report for tt " + ttnum,'a')):

open("WiFi Logs report for tt " + ttnum,'a')

With extra parentheses, you pass one argument to open, and this argument is a tuple: a pair of values, which is not what open expects for its first argument.

A side note (unrelated to your error): you don't have to chdir before you read a file (and your actual code only works when filename is already absolute, which the result of tk_getOpenFile is. chdir doesn't help anything here). And when chdir is necessary, it's error-prone (it introduces hidden state) and thread-unsafe.