input: from typing import List, Tuple
  
  def extract_emails(text: str) -> List[Tuple[str, str]]:
      """ Extract all email addresses from a given string and return a list of tuples.
      Each tuple should contain the email address and the domain name extracted from the email.
      >>> extract_emails("This is an example with two emails: john@example.com, and jane@example.com")
      [('john@example.com', 'example.com'), ('jane@example.com', 'example.com')]
      """
output:     import re
      emails = re.findall(r'[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}', text)
      result = []
      for email in emails:
          domain = email.split('@')[1]
          result.append((email, domain))
      return result