input: Write a function to extract all email addresses from a given string. Use regular expressions to identify and return a list of email addresses found in the input string.
  
  import re
  
  def find_emails(text):
      regex = r"([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)"
      emails = re.findall(regex, text)
      return emails
  
  assert find_emails("This is an example with two emails: john@example.com, and jane@example.com")==['john@example.com', 'jane@example.com']
  assert find_emails("No emails in this string")==[]
  assert find_emails("Contact us at info@company.com or support@domain.org")==['info@company.com', 'support@domain.org']
  assert find_emails("")==[]
  assert find_emails("Multiple emails: alice@test.com, bob@another.org, charlie@subdomain.another.org")==['alice@test.com', 'bob@another.org', 'charlie@subdomain.another.org']
output: def find_emails(text):
      regex = r"([a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+)"
      emails = re.findall(regex, text)
      return emails