code: def get_column_metadata(gctx_file_path, convert_neg_666=True):
      
      full_path = os.path.expanduser(gctx_file_path)
      # open file
      gctx_file = h5py.File(full_path, "r")
      col_dset = gctx_file[col_meta_group_node]
      col_meta = parse_metadata_df("col", col_dset, convert_neg_666)
      gctx_file.close()
      return col_meta
docs: Opens .gctx file and returns only column metadata
  
      Input:
          Mandatory:
          - gctx_file_path (str): full path to gctx file you want to parse.
  
          Optional:
          - convert_neg_666 (bool): whether to convert -666 values to num
  
      Output:
          - col_meta (pandas DataFrame): a DataFrame of all column metadata values.