code: def create_precursor_quant_lookup(quantdb, mzmlfn_feats, quanttype,
                                    rttol, mztol, mztoltype):
      
      featparsermap = {'kronik': kronik_featparser,
                       'openms': openms_featparser,
                       }
      features = []
      mzmlmap = quantdb.get_mzmlfile_map()
      for specfn, feat_element in mzmlfn_feats:
          feat = featparsermap[quanttype](feat_element)
          features.append((mzmlmap[specfn], feat['rt'], feat['mz'],
                           feat['charge'], feat['intensity'])
                          )
          if len(features) == DB_STORE_CHUNK:
              quantdb.store_ms1_quants(features)
              features = []
      quantdb.store_ms1_quants(features)
      quantdb.index_precursor_quants()
      align_quants_psms(quantdb, rttol, mztol, mztoltype)
docs: Fills quant sqlite with precursor quant from:
          features - generator of xml features from openms