-# Get the name of the first file in the collection
-input_file = list(input_collection.all_files())[0].name()
-
-# Extract the file to a temporary directory
-# Returns the directory that the file was written to
-input_dir = arvados.util.collection_extract(this_task_input,
- 'tmp',
- files=[input_file],
- decompress=False)
-
-# Run the external 'md5sum' program on the input file, with the current working
-# directory set to the location the input file was extracted to.
-stdoutdata, stderrdata = arvados.util.run_command(
- ['md5sum', input_file],
- cwd=input_dir)
-
-# Save the standard output (stdoutdata) "md5sum.txt" in the output collection