input: Write a function to clean up a list of emails and put them into a new list. The function should remove any '+' and everything after it in the email, and remove '.uk' if it exists. If the given list is empty, it should return an empty list.
  assert clean_emails(['bob@example.com', 'alice+bob@cafe.com', 'bob@gmail.com.uk', 'bob+alice@example'])==['bob@example.com', 'alice@cafe.com', 'bob@gmail.com', 'bob@example']
  assert clean_emails([])==[]
  assert clean_emails(['john.doe@gmail.uk', 'jane+doe@hotmail.com'])==['john.doe@gmail', 'jane@hotmail.com']
output: def clean_emails(emails):
      cleaned_emails = []
      for email in emails:
          if '+' in email:
              email = email.split('+', 1)[0]
          if '.uk' in email:
              email = email.replace('.uk', '')
          cleaned_emails.append(email)
      return cleaned_emails