IOError: [Errno 22] invalid mode ('r') or filename: 'c:\Python27 est.txt'

Question

What is wrong with the following: ``` test_file=open('c:\Python27	est.txt','r') ```

Accepted Answer

`	` is a tab character. Use a raw string instead:

```
test_file=open(r'c:\Python27	est.txt','r')
```

or double the slashes:

```
test_file=open('c:\Python27\test.txt','r')
```

or use forward slashes instead:

```
test_file=open('c:/Python27/test.txt','r')
```

IOError: [Errno 22] invalid mode ('r') or filename: 'c:\\Python27\test.txt'