<s> class FeatureNotFoundError ( Exception ) : <EOL> """<STR_LIT>""" <EOL> def __init__ ( self , feature_id ) : <EOL> Exception . __init__ ( self ) <EOL> self . feature_id = feature_id <EOL> def __str__ ( self ) : <EOL> return self . feature_id <EOL> class DuplicateIDError ( Exception ) : <EOL> pass <EOL> class AttributeStringError ( Exception ) : <EOL> pass </s>
