Although this field inherits from FieldItem, it
does not have a .scanField() method, just a .flatten() method used when writing the output record.
For code values, see the
specification.
# - - - - - c l a s s C a p t u r e C o d e F i e l d - - - - -
class CaptureCodeField(FieldItem):
'''Represents a capture code that identifies the encounter type.
Exports: as inherited.
'''