ALL = 'all'

NO_UNITS = 'no_units'

START_DT = 'start_dt'

END_DT = 'end_dt'

SEG_ID = 'seg_id'

CUSTOM_FILTER = 'custom'

NO_SEGMENT = -1

FEATURE_LEVEL = 'feature'

class variable_type(object):

    QUANTITATIVE = 'qn'

    ORDINAL = 'ord'

    NOMINAL = 'nom'

class clinical_source(object):

    INTERVENTION = 'intervention'

    OBSERVATION = 'observation'

class column_names:

    UNITS='units'

    VALUE='value'

    ID='id'

    DATETIME='datetime'

    DESCRIPTION='description'

    COMPONENT='component'

    VAR_TYPE = 'variable_type'

    CLINICAL_SOURCE = 'clinical_source'