Removed unnecessary if statement in createsuperuser command.

                # Get a password

                while password is None:

                    if not password:

                    password = getpass.getpass()

                    password2 = getpass.getpass(force_str('Password (again): '))

                    if password != password2:

                        self.stderr.write("Error: Your passwords didn't match.")

                        password = None

                        continue

                    if password.strip() == '':

                        self.stderr.write("Error: Blank passwords aren't allowed.")

                        password = None