Write a function print_dim that takes a DataFrame object and prints out the text 'This DataFrame contains X rows and Y columns', where X and Y are the number of rows and columns in the DataFrame.
For example, for a DataFrame like this
+--------+---------------+-------------------+
| | Title | Author |
|--------+---------------+-------------------|
| Year | | |
|--------+---------------+-------------------|
| 1877 | Anna Karenina | Leo Tolstoy |
| 1815 | Emma | Jane Austen |
| 1860 | Little Women | Louisa May Alcott |
| 1847 | Jane Eyre | Charlotte Brontë |
+--------+---------------+-------------------+the output should be: This DataFrame contains 4 rows and 2 columns(note that 'Year' is an index here).
