pep8 fix for Shippable

lib/ansible/modules/network/nxos/nxos_rollback.py

@@ -81,6 +81,7 @@ status:
 from ansible.module_utils.nxos import nxos_argument_spec, run_commands
 from ansible.module_utils.basic import AnsibleModule
 
+
 def checkpoint(filename, module):
     commands = ['terminal dont-ask', 'checkpoint file %s' % filename]
     run_commands(module, commands)