Update README.rst

Author: timthelion

README.rst

@@ -49,7 +49,9 @@ A fully configured example project can be found in the example directory of this
     The available parameters are `app_label`, `model_name`, and `resource`. 'resource' should be a function which returns a django-import-export `Resource <https://django-import-export.readthedocs.io/en/latest/api_resources.html>`__.
 
 3. Done
-4. Configure to turn off default dry run import. By default dry run import is `True`
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+By default a dry run of the import is initiated when the import object is created. To instead import the file immediately without a dry-run set the `IMPORT_DRY_RUN_FIRST_TIME` to `False`
 
     ::