How do I use tabs and spaces? (how to resolve error TabError: inconsistent)

[deanhystad]

When you run the program you need to pass an argument. The program checks this, but in the wrong place. Your code should look like this:

if len(sys.argv) < 2:
    print "No input file name given!"
    exit()
bank = Bank(sys.argv[1])
bank.gencsvk()

Now if you forget to provide a filename you will get the informative message "No input file name given!" instead of an obscure error message about index out of range.

To use this program you will use a command like "python knab.py somefilename" where "somefilename" is the name of a file that appears to contain transactions.