input: Write a python function to fetch the content of a webpage and handle the status code.
  assert fetch_webpage("https://www.example.com/") is not None
  assert fetch_webpage("https://nonexistent-url.com/") == "Error fetching the page"
output: import requests
  
  def fetch_webpage(url):
      try:
          response = requests.get(url)
          response.raise_for_status()
          return response.text
      except requests.RequestException:
          return "Error fetching the page"