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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 add_suffix(in_files, suffix):
 """ Wrap nipype's fname_presuffix to conveniently just add a prefix 'sub-045_ses-test_T1w_test.nii.gz' """

    import os.path as op
    from nipype.utils.filemanip import fname_presuffix, filename_to_list
    return op.basename(fname_presuffix(filename_to_list(in_files)[0],
                                       suffix=suffix))