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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _symlink_or_copy_grabix(in_file, out_file, data):
 """We cannot symlink in CWL, but may be able to use inputs or copy """

    if cwlutils.is_cwl_run(data):
        # Has grabix indexes, we're okay to go
        if utils.file_exists(in_file + ".gbi"):
            out_file = in_file
        else:
            utils.copy_plus(in_file, out_file)
    else:
        utils.symlink_plus(in_file, out_file)
    return out_file