code: def versionstring():
      # type: () -> Text
      '''
      version of CWLtool used to execute the workflow.
      '''
      pkg = pkg_resources.require("cwltool")
      if pkg:
          return u"%s %s" % (sys.argv[0], pkg[0].version)
      return u"%s %s" % (sys.argv[0], "unknown version"f versionstring():
      # type: () -> Text
      '''
      version of CWLtool used to execute the workflow.
      '''
      pkg = pkg_resources.require("cwltool")
      if pkg:
          return u"%s %s" % (sys.argv[0], pkg[0].version)
      return u"%s %s" % (sys.argv[0], "unknown version")
docs: version of CWLtool used to execute the workflow.