Supporting check mode

To indicate that a module supports check mode, an argument has to be set when creating the module object. This can be done before or after the argument_spec variable is defined in the module object; here, we will do it after it is defined:

    module = AnsibleModule( 
        argument_spec = dict( 
            source=dict(required=True, type='str'), 
            dest=dict(required=True, type='str') 
        ), 
        supports_check_mode=True 
    ) 

If you're modifying your existing code, don't forget to add the comma after the argument_spec dictionary definition, as shown in the preceding code.