input: Write a function to extract all email addresses from a given string using regular expressions. If the given string is empty, then return an empty list.
  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("")==[]
  assert find_emails("No emails here")==[]
  assert find_emails("Email at info@company.com and another at support@company.net")==['info@company.com', 'support@company.net']
  assert find_emails("Mixed with text: address@domain, invalid@domain@part")==['address@domain']
output: 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