Update index.rst

docs/index.rst

@@ -31,17 +31,17 @@ Tablib is an :ref:`MIT Licensed <mit>` format-agnostic tabular dataset library,
    ...     data.append(i)
 
 
-   >>> print(data.json)
+   >>> print(data.export('json'))
    [{"Last Name": "Reitz", "First Name": "Kenneth", "Age": 22}, {"Last Name": "Monke", "First Name": "Bessie", "Age": 21}]
 
    >>> print(data.yaml)
    - {Age: 22, First Name: Kenneth, Last Name: Reitz}
    - {Age: 21, First Name: Bessie, Last Name: Monke}
 
-   >>> data.xlsx
+   >>> data.export('xlsx')
    <censored binary data>
 
-   >>> data.df
+   >>> data.export('df')
      First Name Last Name  Age
    0    Kenneth     Reitz   22
    1     Bessie     Monke   21