docs: def add_new_enriched_bins_matrixes(region_files, dfs, bin_size):
  
      """Add enriched bins based on bed files.
  
      There is no way to find the correspondence between region file and matrix
      file, but it does not matter."""
  
      dfs = _remove_epic_enriched(dfs)
  
      names = ["Enriched_" + os.path.basename(r) for r in region_files]
  
      regions = region_files_to_bins(region_files, names, bin_size)
  
      new_dfs = OrderedDict()
  
      assert len(regions.columns) == len(dfs)
      for region, (n, df) in zip(regions, dfs.items()):
  
          region_col = regions[region]
  
          df = df.join(region_col, how="outer").fillna(0)
  
          new_dfs[n] = df
  
      return new_dfs