code: def cwlout(key, valtype=None, extensions=None, fields=None, exclude=None):
      
      out = {"id": key}
      if valtype:
          out["type"] = valtype
      if fields:
          out["fields"] = fields
      if extensions:
          out["secondaryFiles"] = extensions
      if exclude:
          out["exclude"] = exclude
      return out
docs: Definition of an output variable, defining the type and associated secondary files.