code: def parse_form_action_url(html, parser=None):
      
      if parser is None:
          parser = bs4.BeautifulSoup(html, 'html.parser')
  
      forms = parser.find_all('form')
      if not forms:
          raise VkParseError('Action form is not found in the html \n%s' % html)
      if len(forms) > 1:
          raise VkParseError('Find more than 1 forms to handle:\n%s', forms)
      form = forms[0]
      return form.get('action')
docs: Parse <form action="(.+)"> url
  
      :param html: str: raw html text
      :param parser: bs4.BeautifulSoup: html parser
      :return: url str: for example: /login.php?act=security_check&to=&hash=12346