#100DaysOfCode in Python Transcripts
Chapter: Days 28-30: Regular Expressions
Lecture: String capturing parenthesis

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0:00 A common task is to capture strings using a regex. Here we have two strings, 100 and 200. What if we want to extract number days of code
0:14 out of these strings. Here's how you would do it. First, I do a research. And I use the capturing parentheses.
0:29 What this will do, any regex inside these parentheses that matches the string will be stored in a match object, which we can access with groups.
0:40 Hashtag, one or more digits, days of code. As it is searched, re is happy to just match the substrings.
0:51 So I don't need make sure that the whole string matches. If this would be match. Let's do it actually.
1:00 I would have to account for anything that comes before, and anything that comes after. Of course I need to give it a string.
1:10 And let's see what happens. So first of all we have a match object, and to get the actual matching string I can do groups.
1:20 And it gives me a tuple of the matches. So to get the actual string, I can just use indexing. And I got 100 days of code.
1:32 Now this will work the same for 200. Let me show search, that was my initial intent. Search, then I don't have to account for end time,
1:44 so I those wild cards out. I'm going to use 200 to show the match object first. And again, 200 days of code.
2:02 So you see the power of regular expressions, this is still very simple. I can just say one or more digits, followed by a string,
2:09 and it will match both 100 and 200 days of code. So that's how you capture strings with the re module.

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