'Books a revision number for current operation in ocr_meta
@param formUUID: uuid of the generated form
@param formResourceName: name of the eden resource'

@staticmethod
def __book_revision(formUUID, formResourceName):

    db = current.db
    table = current.s3db.ocr_meta
    import uuid
    revision = uuid.uuid5(formUUID, formResourceName).hex.upper()[:6]
    table.insert(form_uuid=formUUID, resource_name=formResourceName, revision=revision)
    return revision
