code: def afni_copy(filename):
      ''' creates a ``+orig`` copy of the given dataset and returns the filename as a string '''
      if nl.pkg_available('afni',True):
          afni_filename = "%s+orig" % nl.prefix(filename)
          if not os.path.exists(afni_filename + ".HEAD"):
              nl.calc(filename,'a',prefix=nl.prefix(filename))
          return afni_filenamf afni_copy(filename):
      ''' creates a ``+orig`` copy of the given dataset and returns the filename as a string '''
      if nl.pkg_available('afni',True):
          afni_filename = "%s+orig" % nl.prefix(filename)
          if not os.path.exists(afni_filename + ".HEAD"):
              nl.calc(filename,'a',prefix=nl.prefix(filename))
          return afni_filename
docs: creates a ``+orig`` copy of the given dataset and returns the filename as a string