# BeautifulSoup

** Package **

; A collection of functions made by someone. It can be installed and used on  Python.

To install a package, 
`!pip install 'Package name'`.

Once it's installed, run `from 'Package name' import 'module'` to use the package.
> module is functions saved in a package.


### BeautifulSoup ###
; often used to do crawling data from websites.

- install the package
```
!pip install beautifulSoup4
```
```
from bs4 import BeautifulSoup
```
> a name used to import a package is not always the same as the one to install the package.

E.g. Web scrapping Code

```
# HTML 문서를 문자열 html로 저장
html = '''
<html> 
    <head> 
    </head> 
    <body> 
        <h1> 장바구니
            <p id='clothes' class='name' title='라운드티'> 라운드티
                <span class = 'number'> 25 </span> 
                <span class = 'price'> 29000 </span> 
                <span class = 'menu'> 의류</span> 
                <a href = 'http://www.naver.com'> 바로가기 </a> 
            </p> 
            <p id='watch' class='name' title='시계'> 시계
                <span class = 'number'> 28 </span>
                <span class = 'price'> 32000 </span> 
                <span class = 'menu'> 액세서리 </span> 
                <a href = 'http://www.facebook.com'> 바로가기 </a> 
            </p> 
        </h1> 
    </body> 
</html>
'''

# BeautifulSoup 인스턴스 생성. 두번째 매개변수는 분석할 분석기(parser)의 종류.
soup = BeautifulSoup(html, 'html.parser')
```

` soup = BeautifulSoup('name of a document', 'type of parser') `

** How to use select()? **
`soup.select('data you are looking for')`
- soup.select('name of tag')
- soup.select('.name of class')
- soup.select('#ID')
- soup.select('name of upper tag' 'name of lower tag')
- soup.select('name of upper tag > name of lower tag')


### Practice ###

- To return body tag.
```
# To return body tag.
print(soup.select('body'))
```
![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1659532543367/DoFlcXyB7.png align="left")


- To return a tag.
```
# To return a tag.
print(soup.select('a'))
```
![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1659532692342/YQRzHGXi7.png align="left")


- To return price.
```
# To return price.
print(soup.select('.price'))
```
![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1659532728547/6qrsCyX2p.png align="left")


- To return 시계 under p tag.
```
# To return 시계 under p tag.
print(soup.select('#watch'))
```
![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1659532846114/rYhHVuNll.png align="left")


- To return price under clothes ID.
```
# To return price under clothes ID.
print(soup.select('#clothes .price'))
```
![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1659532961113/jkUT68FtA.png align="left")


** `soup.'name of tag'`**
; used to show the first tag used in HTML until that specific tag ends.
```
soup.a
```
![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1659533132110/Zyr4V5QL6.png align="left")


** `soup.'name of tag'.get('type')**
; used to show the value of the type.
```
soup.a.get('href')
```
![image.png](https://cdn.hashnode.com/res/hashnode/image/upload/v1659533309070/nJqlTiq4w.png align="left")