Why does the first function return True? Shouldn't it return the file content? That's at least what the function name implies. You call the second function open_command() which returns a boolean. Feels wrong.
Where you have written "How?" I suggest that you replace that by: return open_file("foo.bar", 1) and change open_file() to look something like this: def open_file(file_name, ignore_lock=False): f = file(file_name, 'r') {read first line for file lock info} if first_line == "FILE LOCKED" and not ignore_lock: raise FileLockedException(lock_user, lock_timestamp) {read remainder of file} return True -- http://mail.python.org/mailman/listinfo/python-list