# Data export
On this page the `data_export` custom django command is described from the developer perspective.
## Entry point of the `data_export` command
When executing the `data_export` command with the `manage.py` management script, django searches in the app-folders of the project for a script withthe name `data_export.py` lieing inside the sub-folder structure `management/commands/`. Inside `data_export.py` a class `Command` is located, which is inherits from the django class `BaseCommand`. Django expects the method `handle` inside that class, which holds the execution logic for the command. Furthermore the optional method `add_arguments` can be added, which adds arguments to the custom management command. Please consult the respective part of the [django documentation](https://docs.djangoproject.com/en/5.0/howto/custom-management-commands/).
The `data_export` command expects as a first argument the name of the app from which structured data should be exported. That name is just the app folder name. 
The `handle`-method checks if a `data_export.py` script is located inside the given app folder and instantiates the `DataExport` class inside this file. That class holds the app specific export functionality. The most importent elements are class constants definied there. That are the `MAPPING_ORM_TO_XLSX` and `EXPORT_MODEL_OBJ` constant. `EXPORT_MODEL_OBJ` holds the ORM-class model, from which data should be exported. `MAPPING_ORM_TO_XLSX`is a mapping between the attribute names of the ORM-model and the column names of a structured data file to which it should be converted.
That means by removing key-value pairs from the dictionary it can be controlled, which attributes are exported to the data file.