input: Write a python function to fetch and parse the current Bitcoin price from a webpage.
  assert fetch_bitcoin_price('https://example.com/') == '50,000'
  assert fetch_bitcoin_price('https://example.com/') == '45,000'
  assert fetch_bitcoin_price('https://example.com/') == '60,000'
output: def fetch_bitcoin_price(url):
      import requests
      from bs4 import BeautifulSoup
  
      response = requests.get(url)
      soup = BeautifulSoup(response.text, 'html.parser')
  
      # This part needs to be adapted according to the actual structure of the webpage
      price_element = soup.find('span', {'class': 'bitcoin-price'})
      if price_element:
          return price_element.text.strip()
      return None