input: Write a python function to extract all headers and paragraphs from a given Wikipedia page.
  assert extract_headers_and_paragraphs("https://en.wikipedia.org/wiki/Wikipedia") is not None
output: def extract_headers_and_paragraphs(url):
      import requests
      from bs4 import BeautifulSoup
  
      response = requests.get(url)
      soup = BeautifulSoup(response.content, 'html.parser')
      
      headers_and_paragraphs = []
  
      for header in soup.find_all(['h1', 'h2', 'h3', 'h4', 'h5', 'h6']):
          headers_and_paragraphs.append(header.get_text(strip=True))
      
      for paragraph in soup.find_all('p'):
          headers_and_paragraphs.append(paragraph.get_text(strip=True))
      
      return headers_and_paragraphs