Mixed-Up Code Questions

Section 13.17 Mixed-Up Code Questions

Checkpoint 13.17.1.

Create a function called decode that takes in a parameter link and returns a string that contains the contents of the link using urllib. Between each word, there should be a space. Also, a space at the end is okay. For example, decode('http://data.pr4e.org/romeo.txt') should return

'But soft what light through yonder window breaks It is the east and Juliet is the sun Arise fair sun and kill the envious moon Who is already sick and pale with grief '

import urllib.request
---
def decode(link):
---
    fhand = urllib.request.urlopen(link)
---
    string = ''
---
    for line in fhand:
---
        string += line.decode().replace('\n', ' ')
---
        string += line.decode().strip()  #paired
---
    return string
---
    return fhand.decode().strip()  #paired

Checkpoint 13.17.2.

Create a function called write_txt that takes in a parameter link, retrieves a file from the link using urllib, and writes the contents of the link to a file called 'clown.txt'. For example, write_txt('http://data.pr4e.org/clown.txt') should create a file called 'clown.txt' that has the string 'the clown ran after the car and the car ran into the tent and the tent fell down on the clown and the car'.

import urllib.request
import os
---
def write_txt(link):
---
    text = urllib.request.urlopen(link).read()
---
    fhand = open(os.path.join(os.path.dirname(__file__), 'clown.txt'), 'wb')
---
    fhand = open(os.path.join(os.path.dirname(__file__), 'clown.txt'), 'w')  #paired
---
    fhand.write(text)
---
    fhand.close()

Checkpoint 13.17.3.

Create a function called count_words that takes in a parameter link, retrieves a file from the link using urllib, and returns a dictionary with words as keys and the number of times they appear in the link as values. For example, count_words('http://data.pr4e.org/romeo.txt') should return

{'But': 1, 'soft': 1, 'what': 1, 'light': 1, 'through': 1, 'yonder': 1, 'window': 1, 'breaks': 1, 'It': 1, 'is': 3, 'the': 3, 'east': 1, 'and': 3, 'Juliet': 1, 'sun': 2, 'Arise': 1, 'fair': 1, 'kill': 1, 'envious': 1, 'moon': 1, 'Who': 1, 'already': 1, 'sick': 1, 'pale': 1, 'with': 1, 'grief': 1}

import urllib.request
---
def count_words(link):
---
    fhand = urllib.request.urlopen(link)
---
    fhand = urllib.request.urlopen(link).read()  #paired
---
    counts = {}
---
    for line in fhand:
---
        words = line.decode().split()
---
        words = line.decode()  #paired
---
        words = line.split() 
---
        for word in words:
---
            counts[word] = counts.get(word, 0) + 1
---
    return counts

Checkpoint 13.17.4.

Create a function called write_jpg that takes in a parameter img_link, retrieves a file from the img_link using urllib, and writes the contents of the img_link to a file called 'cover.jpg'. For example, write_jpg('http://data.pr4e.org/cover3.jpg') should create a file called 'cover.jpg' that has an image of the cover for "PYTHON FOR EVERYBODY".

import urllib.request
import os
---
def write_jpg(img_link):
---
    img = urllib.request.urlopen(img_link).read()
---
    fhand = open(os.path.join(os.path.dirname(__file__), 'cover.jpg'), 'wb')
---
    fhand = open(os.path.join(os.path.dirname(__file__), 'cover.jpg'), 'w')  #paired
---
    fhand = open(os.path.join(os.path.dirname(__file__), 'cover.jpg'), 'r') 
---
    fhand.write(img)
---
    fhand.close()

Checkpoint 13.17.5.

Create a function called num_chars that takes in a parameter link, retrieves a file from the link using urllib, and returns the number of characters in link in the format "(num) characters". For example, num_chars('http://data.pr4e.org/romeo-full.txt') should return "8864 characters".

import urllib.request
---
def num_chars(link):
---
    txt = urllib.request.urlopen(link)
---
    num = len(txt.read())
---
    num = len(txt.decode())  #paired
---
    num = len(txt) 
---
    return str(num) + ' characters'
---
    return num + ' characters'  #paired

Checkpoint 13.17.6.

Create a function called contents that takes in a parameter link, retrieves a file from the link using sockets, and returns as a string the contents of the link (specifically 10000 characters). For example, contents('http://data.pr4e.org/clown.txt') should return

"HTTP/1.1 200 OK\nDate: Thu, 12 Aug 2021 01:24:15 GMT\nServer: Apache/2.4.18 (Ubuntu)\nLast-Modified: Sat, 13 May 2017 11:22:22 GMT\nETag: '6a-54f6609240717'\nAccept-Ranges: bytes\nContent-Length: 106\nCache-Control: max-age=0, no-cache, no-store, must-revalidate\nPragma: no-cache\nExpires: Wed, 11 Jan 1984 05:00:00 GMT\nConnection: close\nContent-Type: text/plain\n\nthe clown ran after the car and the car ran into the tent and the tent fell down on the clown and the car\n"

import socket
---
def contents(link):
---
    mysock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
---
    mysock.connect(('data.pr4e.org', 80))
---
    cmd = 'GET ' + link + ' HTTP/1.0\r\n\r\n'
---
    cmd = 'GET ' + link + ' HTTP/1.0\r\n\r\n'.encode()  #paired
---
    cmd = cmd.encode()
---
    mysock.send(cmd)
---
    data = mysock.recv(10000)
---
    data = mysock.recv()  #paired
---
    return data.decode()
---
    return data  #paired
---
    mysock.close()

Checkpoint 13.17.7.

Create a function called reg_num_links that takes in a parameter url and returns the number of ‘href' attributes that start with ‘http' using regular expressions. Since websites are frequently updated, the returned number may change as links get added and deleted.

import urllib.request
import re
---
def reg_num_links(url):
---
    html = urllib.request.urlopen(url).read()
---
    html = urllib.request.urlopen(url)  #paired
---
    links = re.findall(b'href="(http[s]?://.*?)"', html)
---
    links = re.findall(b'href="(http.*)"', html)  #paired
---
    return len(links)

Checkpoint 13.17.8.

Create a function called bsoup_num_links that takes in a parameter url and returns the number of ‘href' attributes that start with ‘http' using BeautifulSoup. Since websites are frequently updated, the returned number may change as links get added and deleted.

import requests
from bs4 import BeautifulSoup
---
def bsoup_num_links(url):
---
    list1 = []
---
    resp = requests.get(url)
---
    soup = BeautifulSoup(resp.content, 'html.parser')
---
    tags = soup.find_all(href=True)
---
    tags = soup.find_all(href)  #paired
---
    tags = soup.find_all('href'=True) 
---
    tags = soup.find_all('href')  #paired
---
    for tag in tags:
---
        if tag.get('href', None).startswith('http'):
---
        if tag.startswith('http'):  #paired
---
            list1.append((tag.get('href', None)))
---
    return len(list1)

Checkpoint 13.17.9.

Create a function called img_links that takes in a parameter url and returns a list that contains all image links using BeautifulSoup. Since websites are frequently updated, the returned list of image links may change as image links get added and deleted.

import requests
from bs4 import BeautifulSoup
---
def img_links(url):
---
    list1 = []
---
    resp = requests.get(url)
---
    soup = BeautifulSoup(resp.content, 'html.parser')
---
    tags = soup.find_all('img')
---
    tags = soup.findall('img')  #paired
---
    for tag in tags:
---
        list1.append(tag.get('src', None))
---
        list1.append(tag)  #paired
---
    return list1

Checkpoint 13.17.10.

Create a function called span_attrs that takes in a parameter url and returns a list of dictionaries using BeautifulSoup. Each dictionary is equivalent to each span tag. The keys of the dictionary are the attributes of the span tag, and the values of the dictionary are the values of the attributes. Since websites are frequently updated, the returned list of dictionaries may change as span tags, attributes, and values get added, deleted, or modified.

import requests
from bs4 import BeautifulSoup
---
def span_attrs(url):
---
    list1 = []
---
    resp = requests.get(url)
---
    soup = BeautifulSoup(resp.content, "html.parser")
---
    tags = soup.find_all('span')
---
    tags = soup.find_all(span)  #paired
---
    for tag in tags:
---
        list1.append(tag.attrs)
---
        list1.append(tag.attributes)  #paired
---
        list1.append({tag.attrs: tag.values}) 
---
        list1.append({tag.attrs(): tag.values()})  #paired
---
        list1.append({tag.attributes: tag.values}) 
---
        list1.append({tag.attributes(): tag.values()})  #paired
---
    return list1

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