def get_attr_values(self, attrlist):
<EOL>attribute_list = getattr(self, attrlist, None)<EOL>if not attribute_list:<EOL><INDENT>return None<EOL><DEDENT>if not isinstance(attribute_list, list):<EOL><INDENT>attribute_list = [attribute_list]<EOL><DEDENT>return [getattr(self, attr, "<STR_LIT>") for attr in attribute_list]<EOL>
Get value corresponding to each given attribute.

:param str attrlist: name of an attribute storing a list of attr names
:return list | NoneType: value (or empty string) corresponding to
    each named attribute; null if this Sample's value for the
    attribute given by the argument to the "attrlist" parameter is
    empty/null, or if this Sample lacks the indicated attribute