input: 
  def extract_data(url: str, tag: str, attribute: str) -> list:
      """ Create a web scraper that extracts specific data from a given website.
      The web scraper should utilize the Python package BeautifulSoup to parse webpages 
      and extract the required data. BeautifulSoup will allow us to find HTML elements 
      on the webpage using tags and attributes. Once the data is found, it can be 
      converted into the desired format and stored.
      
      >>> extract_data("<url_of_webpage>", "a", "href")
      ['<first_url>', '<second_url>', ...]
      """
  
output:     
      import requests
      from bs4 import BeautifulSoup
  
      response = requests.get(url)
      soup = BeautifulSoup(response.text, 'html.parser')
      elements = soup.find_all(tag)
      data = [element.get(attribute) for element in elements if element.get(attribute)]
      return data
  