input: from typing import List
  
  def extract_urls(webpage_urls: List[str]) -> List[str]:
      """Extract URLs from a list of webpage URLs using BeautifulSoup.
      >>> extract_urls(["<url_of_webpage1>", "<url_of_webpage2>"])
      ['http://example.com/1', 'http://example.com/2']
      """
      import requests
      from bs4 import BeautifulSoup
      urls = []
      for url in webpage_urls:
          webpage = requests.get(url)
          soup = BeautifulSoup(webpage.content, 'html.parser')
          links = soup.find_all('a')
          for link in links:
              urls.append(link.get('href'))
      return urls
output:     import requests
      from bs4 import BeautifulSoup
      urls = []
      for url in webpage_urls:
          webpage = requests.get(url)
          soup = BeautifulSoup(webpage.content, 'html.parser')
          links = soup.find_all('a')
          for link in links:
              href = link.get('href')
              if href and href.startswith('http'):
                  urls.append(href)
      return urls