docs: def table_type(table_name):
      """
      Returns the type of a registered table.
  
      The type can be either "dataframe" or "function".
  
      Parameters
      ----------
      table_name : str
  
      Returns
      -------
      table_type : {'dataframe', 'function'}
  
      """
      table = get_raw_table(table_name)
  
      if isinstance(table, DataFrameWrapper):
          return 'dataframe'
      elif isinstance(table, TableFuncWrapper):
          return 'function'