## FieldIndex.letter_range property Gets or sets a range of letters to which limit the index. ```python @property def letter_range(self) -> str: ... @letter_range.setter def letter_range(self, valu......FIELD_INDEX, update_field=True).as_field_index()...FieldType.FIELD_INDEX_ENTRY, update_field=True).as_field_xe() index_entry...