> '$output' &&
## verify that ext is "data" for absent optional input
echo INPUT ext $names.ext >> '$output' &&
## verify that is_of_type for absent optional input
## does not evaluate to True for any of the allowed datatypes
echo ISOFTYPE mothur.names $names.is_of_type("mothur.names") >> '$output' &&
echo ISOFTYPE mothur.count_table $names.is_of_type("mothur.count_table") >> '$output'
]]>