input: Write a function to create a web scraper in Python that can extract hotel reviews from TripAdvisor. The function should take a URL as input, make a request to that URL using custom headers, parse the HTML content using BeautifulSoup, find and extract all review titles and texts, and print them. If no reviews are found, it should print a message indicating that no reviews were found.
  
  def scrape_hotel_reviews(url):
      import requests
      from bs4 import BeautifulSoup
  
      # Define the headers
      headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36'}
  
      # Make a request and get HTML in response
      response = requests.get(url, headers=headers)
  
      # Parse HTML
      soup = BeautifulSoup(response.text, 'html.parser')
  
      # Find all reviews
      reviews = soup.find_all('div', {'class': 'review-container'})
  
      if not reviews:
          print("No reviews found.")
          return
  
      # Go through every review and extract the data
      for review in reviews:
          # Get the title
          title = review.find('span', {'class': 'noQuotes'}).text
  
          # Get the text
          text = review.find('p', {'class': 'partial_entry'}).text
  
          # Print for demo
          print(title)
          print(text)
          print('-' * 50)
  
  assert scrape_hotel_reviews('<valid_url_with_reviews>') == None
  assert scrape_hotel_reviews('<invalid_url>') == None
  assert scrape_hotel_reviews('<url_without_reviews>') == None
output: def scrape_hotel_reviews(url):
      import requests
      from bs4 import BeautifulSoup
  
      headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.138 Safari/537.36'}
  
      response = requests.get(url, headers=headers)
  
      soup = BeautifulSoup(response.text, 'html.parser')
  
      reviews = soup.find_all('div', {'class': 'review-container'})
  
      if not reviews:
          print("No reviews found.")
          return
  
      for review in reviews:
          title = review.find('span', {'class': 'noQuotes'}).text
          text = review.find('p', {'class': 'partial_entry'}).text
          print(title)
          print(text)
          print('-' * 50)