RVSNUpy measures spectroscopic redshifts using inverse-variance-weighted cross-correlation between an observed spectrum and a library of rest-frame template spectra. It ingests spectra (e.g., SDSS FITS spectra and MMT/Hectospec raw spectra) and runs single-object or batch redshift measurements through a reusable measurement object initialized with a chosen template set. RVSNUpy reports redshift solutions across templates and identifies a best measurement within its returned results table. The package includes notebooks demonstrating typical workflows for redshift measurement and inspection of cross-correlation outputs.