how to view/print variable created using set/multiMap

[complexgenome]

I've a CSV file I'd like to read. The file has sample ID, WES normal R1, WES normal R2, WES tumor R1, WES tumor R2, RNA normal R1, RNA normal R2 FASTQ files.

I'd like to see/view the contents of the variable I've created/set. I've below code:

process split_file {

output:stdout

script:

def csv_file=file("../upgraded_split_csv/wes_rna.csv")

Channel.fromPath( csv_file )
        .splitCsv( )
                .multiMap { row ->
                def rna=tuple(file(row[5]), file(row[6]))
            def tumor_reads = tuple( file( row[3]) ,file(row[4]))
            def normal_reads = tuple(file(row[1]),file(row[2]) )
            
            tumor:
                tuple( row[0], tumor_reads )
            normal:
                tuple( row[0], normal_reads )
        }.view()

"""
echo "helo\n"

"""
}

workflow {
split_file()
}

I can't get it working. I get error as:

ERROR ~ Error executing process > 'split_file'

Caused by:
No signature of method: nextflow.extension.OperatorImpl.view() is applicable for argument types: (groovyx.gpars.dataflow.stream.DataflowStreamReadAdapter, groovyx.gpars.dataflow.stream.DataflowStreamReadAdapter) values: [DataflowStream[?], DataflowStream[?]]
Possible solutions: view(groovyx.gpars.dataflow.DataflowReadChannel), view(groovyx.gpars.dataflow.DataflowReadChannel, groovy.lang.Closure), view(groovyx.gpars.dataflow.DataflowReadChannel, java.util.Map), view(groovyx.gpars.dataflow.DataflowReadChannel, java.util.Map, groovy.lang.Closure), grep(), find() -- Check script 'split_csv.nf' at line: 9

How do I do what to print/dump the elements in the samples/multiMap variable?