question: public boolean isDefaultValueMutable ( Field field ) { TypeRef type = field . getType ( ) ; if ( type . getCardinality ( ) == Cardinality . REPEATED ) { return true ; } switch ( type . getKind ( ) ) { case TYPE_MESSAGE : case TYPE_ENUM : return true ; default : return false ; } }
target:  Return whether the given field's default value is mutable in python. 