input: Write a python function to crawl a given URL and find all the unique URLs present in the page.
  assert crawl_and_get_urls('http://www.example.com/search?q=artificial+intelligence')=={'http://www.example.com/link1', 'http://www.example.com/link2'}
  assert crawl_and_get_urls('http://www.example.com/search?q=machine+learning')=={'http://www.example.com/link3', 'http://www.example.com/link4'}
  assert crawl_and_get_urls('http://www.example.com/search?q=deep+learning')=={'http://www.example.com/link5', 'http://www.example.com/link6'}
output: def crawl_and_get_urls(url):
      import requests
      from bs4 import BeautifulSoup
      from urllib.parse import urljoin
  
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
      urls = set()
  
      for link in soup.find_all('a', href=True):
          full_url = urljoin(url, link['href'])
          urls.add(full_url)
  
      return urls