code: def read_table(filename, sheetname, index_col=None):
      
      # Catch sheetname as list or None
      if sheetname is None or \
              (hasattr(sheetname, '__iter__') \
              and not isinstance(sheetname, six.string_types)):
          raise TypeError("sheetname should specify a single sheet")
  
      # Load excel table using pandas
      # Parameter specifying sheet name is slightly different depending on pandas'
      # version.
      if packaging.version.parse(pd.__version__) \
                  < packaging.version.parse('0.21'):
          table = pd.read_excel(filename,
                                sheetname=sheetname,
                                index_col=index_col)
      else:
          table = pd.read_excel(filename,
                                sheet_name=sheetname,
                                index_col=index_col)
      # Eliminate rows whose index are null
      if index_col is not None:
          table = table[pd.notnull(table.index)]
      # Check for duplicated rows
      if table.index.has_duplicates:
          raise ValueError("sheet {} on file {} contains duplicated values "
                           "for column {}".format(sheetname, filename, index_col))
  
      return table
docs: Return the contents of an Excel table as a pandas DataFrame.
  
      Parameters
      ----------
      filename : str
          Name of the Excel file to read.
      sheetname : str or int
          Name or index of the sheet inside the Excel file to read.
      index_col : str, optional
          Column name or index to be used as row labels of the DataFrame. If
          None, default index will be used.
  
      Returns
      -------
      table : DataFrame
          A DataFrame containing the data in the specified Excel table. If
          `index_col` is not None, rows in which their `index_col` field
          is empty will not be present in `table`.
  
      Raises
      ------
      ValueError
          If `index_col` is specified and two rows contain the same
          `index_col` field.