I have an array like below:

```
[
  'author/2020/01/01/all_authors_000.csv',
  'book/2020/01/01/all_books_000.csv',
  'book/2020/01/01/all_books_001.csv',
  'book/2020/01/01/all_books_002.csv',
  'others/2020/01/01/other_stuff.csv',
]

```

As you can see there are three items that start with the word `book`. I want to remove all but one, so I end up with something like:

```
[
  'author/2020/01/01/all_authors_000.csv',
  'book/2020/01/01/all_books_000.csv',
  'others/2020/01/01/other_stuff.csv',
]

```

How can I achieve this?