def auto_to_integer(field):
_field = BigIntegerField()
_field.name = field.attname
_field.db_index = field.db_index
_field.verbose_name = field.verbose_name
_field.db_column = field.db_column
_field.db_tablespace = field.db_tablespace
_field.primary_key = field.primary_key
_field.serialize = field.serialize
_field.null = field.null
_field._unique = field._unique
_field.unique_for_date = field.unique_for_date
_field.unique_for_month = field.unique_for_month
_field.unique_for_year = field.unique_for_year
return _field