Python Tips

IOError: [Errno 22] invalid mode ('r') or filename

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

source:http://stackoverflow.com/questions/15598160/ioerror-errno-22-invalid-mode-r-or-filename-c-python27-test-txt