new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  # emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: nil -*-
  # vi: set ft=python sts=4 ts=4 sw=4 et:
  
  from __future__ import print_function, division, absolute_import, unicode_literals
  
  from nipype.interfaces.base import File, traits, CommandLine, TraitedSpec, CommandLineInputSpec
  
  class GCORInputSpec(CommandLineInputSpec):
      in_file = File(
          desc='input dataset to compute the GCOR over',
          argstr='-input %s',
          position=-1,
          mandatory=True,
          exists=True,
          copyfile=False)
  
      mask = File(
          desc='mask dataset, for restricting the computation',
          argstr='-mask %s',
          exists=True,
          copyfile=False)
  
      nfirst = traits.Int(0, argstr='-nfirst %d',
                          desc='specify number of initial TRs to ignore')
      no_demean = traits.Bool(False, argstr='-no_demean',
                              desc='do not (need to) demean as first step')
  
  
  class GCOROutputSpec(TraitedSpec):
      out = traits.Float(desc='global correlation value')
  
  
  class GCOR(CommandLine):
      """
      Computes the average correlation between every voxel
      and ever other voxel, over any give mask.
      For complete details, see the `@compute_gcor Documentation.
      <https://afni.nimh.nih.gov/pub/dist/doc/program_help/@compute_gcor.html>`_
      Examples
      ========
      >>> from nipype.interfaces import afni
      >>> gcor = afni.GCOR()
      >>> gcor.inputs.in_file = 'structural.nii'
      >>> gcor.inputs.nfirst = 4
      >>> gcor.cmdline  # doctest: +ALLOW_UNICODE
      '@compute_gcor -nfirst 4 -input structural.nii'
      >>> res = gcor.run()  # doctest: +SKIP
      """
  
      _cmd = '@compute_gcor'
      input_spec = GCORInputSpec
      output_spec = GCOROutputSpec
  
      def _run_interface(self, runtime):
          runtime = super(GCOR, self)._run_interface(runtime)
  
          gcor_line = [line.strip() for line in runtime.stdout.split('\n')
                       if line.strip().startswith('GCOR = ')][-1]
          setattr(self, '_gcor', float(gcor_line[len('GCOR = '):]))
          return runtime
  
      def _list_outputs(self):
          return {'out': getattr(self, '_gcor')}
  
subject: add transitional submodule