'Find partners related to some header fields of the message.
:param string message: an email.message instance'

def _message_find_partners(self, message, header_fields=['From']):

    s = ',    '.join([tools.decode_smtp_header(message.get(h)) for h in header_fields if message.get(h)])
    return filter((lambda x: x), self._find_partner_from_emails(tools.email_split(s)))
