def _resolve_value(self, name):
for instance in self.__instances():<EOL><INDENT>value = instance._resolve_value(name)<EOL>if value:<EOL><INDENT>return value<EOL><DEDENT><DEDENT>if name in self.__metadata._meta.elements:<EOL><INDENT>populate_from = self.__metadata._meta.elements[name].populate_from<EOL>if callable(populate_from):<EOL><INDENT>return populate_from(None)<EOL><DEDENT>elif isinstance(populate_from, Literal):<EOL><INDENT>return populate_from.value<EOL><DEDENT>elif populate_from is not NotSet:<EOL><INDENT>return self._resolve_value(populate_from)<EOL><DEDENT><DEDENT>
Returns an appropriate value for the given name. 
            This simply asks each of the instances for a value.