input: Write a python function to fetch and parse all href values for 'a' tags from a given URL.
  assert fetch_href_links("https://example.com/") == ['link1', 'link2', 'link3']
  assert fetch_href_links("https://test.com/") == ['testlink1', 'testlink2']
output: def fetch_href_links(url):
      import requests
      from bs4 import BeautifulSoup
  
      response = requests.get(url)
      soup = BeautifulSoup(response.text, 'html.parser')
      links = [a.get('href') for a in soup.find_all('a') if a.get('href') is not None]
      return links