class NwarpAdjustInputSpec(AFNICommandInputSpec):
    warps = InputMultiPath(
        File(exists=True),
        minlen=5,
        mandatory=True,
        argstr='-nwarp %s',
        desc='List of input 3D warp datasets')
    in_files = InputMultiPath(
        File(exists=True),
        minlen=5,
        argstr='-source %s',
        desc='List of input 3D datasets to be warped by the adjusted warp '
             'datasets.  There must be exactly as many of these datasets as '
             'there are input warps.')
    out_file = File(
        desc='Output mean dataset, only needed if in_files are also given. '
             'The output dataset will be on the common grid shared by the '
             'source datasets.',
        argstr='-prefix %s',
        name_source='in_files',
        name_template='%s_NwarpAdjust',
        keep_extension=True,
        requires=['in_files'])