input: def find_emails(text: str) -> list:
      """
      Extracts all email addresses from a given string.
      >>> find_emails("This is an example with two emails: john@example.com, and jane@example.com")
      ['john@example.com', 'jane@example.com']
      >>> find_emails("No emails in this string.")
      []
      """
output:     import re
      pattern = r'[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}'
      return re.findall(pattern, text)