get_value ( ATTR [, OPTIONS ] )
           Get the values for the attribute ATTR. In a list
           context returns all values for the given attribute, or
           the empty list if the attribute does not exist. In a
           scalar context returns the first value for the
           attribute or undef if the attribute does not exist.

           The return value may be changed by OPTIONS, which is a
           list of name => value pairs, valid options are :-