input: Write a python function to scrape all prices from a given URL using BeautifulSoup.
  assert scrape_prices('https://www.example.com') == ['$19.99', '$29.99', '$39.99']
  assert scrape_prices('https://www.example.com/products') == ['$49.99', '$59.99']
  assert scrape_prices('https://www.example.com/sale') == ['$9.99', '$14.99', '$24.99']
output: def scrape_prices(url):
      import requests
      from bs4 import BeautifulSoup
  
      response = requests.get(url)
      soup = BeautifulSoup(response.text, 'html.parser')
      prices = []
      
      for price in soup.find_all(class_='price'):  # assuming prices are marked with 'price' class
          prices.append(price.text.strip())
      
      return prices