def METHOD_NAME(self, app):
    app_flds = {}
    app_fields_meta = app._meta.get_fields()
    for fm in app_fields_meta:
        if isinstance(fm, (CharField, URLField, DateTimeField, TextField, BooleanField, BigIntegerField, EmailField)):
            fld_name = fm.name
            fld_val = fm.value_from_object(app)
            if fld_val is None and fm.null:
                # if nullable set init value to None
                app_flds[fld_name] = None
            app_flds[fld_name] = fld_val
    return app_flds