Update 05_pet_breeds.ipynb

Changed:

- and then an_character -->> and then an _ character

- same linguist Noam Chomskey -->> same linguist Noam Chomsky

05_pet_breeds.ipynb

@@ -145,7 +145,7 @@
    "source": [
     "Most functions and methods in fastai which return a collection use a class called `L`. `L` can be thought of as an enhanced version of the ordinary Python `list` type, with added conveniences for common operations. For instance, when we display an object of this class in a notebook it appears in the format you see above. The first thing that is shown is the number of items in the collection, prefixed with a `#`. You'll also see in the above output that the list is suffixed with a \"…\". This means that only the first few items are displayed — which is a good thing, because we would not want more than 7000 filenames on our screen!\n",
     "\n",
-    "By examining these filenames, we see how they appear to be structured. Each file name contains the pet breed, and then an_character, a number, and finally the file extension. We need to create a piece of code that extracts the breed from a single `Path`. Jupyter notebook makes this easy, because we can gradually build up something that works, and then use it for the entire dataset. We do have to be careful to not make too many assumptions at this point. For instance, if you look carefully you may notice that some of the pet breeds contain multiple words, so we cannot simply break at the first `_` character that we find. To allow us to test our code, let's pick out one of these filenames:"
+    "By examining these filenames, we see how they appear to be structured. Each file name contains the pet breed, and then an _ character, a number, and finally the file extension. We need to create a piece of code that extracts the breed from a single `Path`. Jupyter notebook makes this easy, because we can gradually build up something that works, and then use it for the entire dataset. We do have to be careful to not make too many assumptions at this point. For instance, if you look carefully you may notice that some of the pet breeds contain multiple words, so we cannot simply break at the first `_` character that we find. To allow us to test our code, let's pick out one of these filenames:"
    ]
   },
   {
@@ -167,7 +167,7 @@
     "\n",
     "We do not have the space to give you a complete regular expression tutorial here, particularly because there are so many excellent ones online. And we know that many of you will already be familiar with this wonderful tool. If you're not, that is totally fine — this is a great opportunity for you to rectify that! We find that regular expressions are one of the most useful tools in our programming toolkit, and many of our students tell us that it is one of the things they are most excited to learn about. So head over to Google and search for *regular expressions tutorial* now, and then come back here after you've had a good look around. The book website also provides a list of our favorites.\n",
     "\n",
-    "> a: Not only are regular expressions dead handy, they also have interesting roots. They are \"regular\" because they were originally examples of a \"regular\" language, the lowest rung within the \"Chomsky hierarchy\", a grammar classification due to the same linguist Noam Chomskey who wrote _Syntactic Structures_, the pioneering work searching for the formal grammar underlying human language. This is one of the charms of computing: it may be that the hammer you reach for every day in fact came from a space ship.\n",
+    "> a: Not only are regular expressions dead handy, they also have interesting roots. They are \"regular\" because they were originally examples of a \"regular\" language, the lowest rung within the \"Chomsky hierarchy\", a grammar classification due to the same linguist Noam Chomsky who wrote _Syntactic Structures_, the pioneering work searching for the formal grammar underlying human language. This is one of the charms of computing: it may be that the hammer you reach for every day in fact came from a space ship.\n",
     "\n",
     "When you are writing a regular expression, the best way to start is just to try it against one example at first. Let's use the `findall` method to try a regular expression against the filename of the `fname` object:"
    ]