With provided URL, it scrawls email addresses within the landing page and the second level pages

email.py

import requests
from bs4 import BeautifulSoup
import re

def extract_email_from_url(url):
    '''
    From the provided url, it extracts all valid email addresses
    :param url: URL to enter
    :return: Set of email addresses in string
    '''
    # enter the URL and retrieved all text
    source_code = requests.get(url)
    plain_text = source_code.text
    soup = BeautifulSoup(plain_text, "html.parser")
    text = soup.text

    # from the text, it collects all valid email addresses
    regex = re.compile(("([a-z0-9!#$%&'*+\/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&'*+\/=?^_`"
                        "{|}~-]+)*(@|\sat\s)(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?(\.|"
                        "\sdot\s))+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?)"))
    emails_tuples = re.findall(regex, text)

    # returns a set of email addresses
    emails = set()
    for email in emails_tuples:
        emails.add(email[0])
    return emails

def get_links(url):
    '''
    From the URL, it returns all the links embedded
    :param url: URL to enter
    :return: Set of links in string
    '''

    source_code = requests.get(url)
    plain_text = source_code.text
    soup = BeautifulSoup(plain_text, "html.parser")
    set_links = set()

    # finds all the links and return them as a list
    for link in soup.findAll('a'):
        href = link.get('href')
        set_links.add(href)
    return set_links

def get_email(url):
    '''
    From the URL, it tries to extract emails from the landing page
    and its 2nd level pages. And it prints all the email addresses it retrieved
    :param url: provided URL from the user
    '''
    emails = set()

    # 1st level
    emails.update(extract_email_from_url(url))

    # 2nd level -- iterate over the set of links
    set_links = get_links(url)
    for link_url in set_links:
        try:
            print("working on: " + link_url)
            emails.update(extract_email_from_url(link_url))
        except requests.exceptions.MissingSchema:
            # some links relative paths, so change them into absolute path
            new_url = url.strip('/') + link_url
            print("working on changed one..." + new_url)
            emails.update(extract_email_from_url(new_url))
        except:
            pass

    # print all email addresses found
    for email in emails:
        print(email)

get_email("https://www.wisc.edu/")

It takes the url, "https://www.wisc.edu", for now