docs: def send_sms(self, frm, to, text):
          """Sends a simple text message.
  
          Example usage::
  
              >>> msg = "Cherie, n'oublie pas les gauffres !"
              >>> nexmo.send_sms('+33123456780', '+33987654321', msg)
  
          :arg frm: The `from` field, a phone number (international format with
              or without a leading "+" or alphanumerical).
          :arg to: The `to` field, a phone number, same format as the `frm`
              argument.
          :arg text: The message body.
  
          See :meth:`send_request` for return value and exceptions.
  
          """
          frm = re.sub('[^\d]', '', frm)
          to = re.sub('[^\d]', '', to)
  
          api_url = '%s/sms/json' % API_ENDPOINT
          params = {
              'api_key': self.api_key,
              'api_secret': self.api_secret,
              'from': frm,
              'to': to,
              'text': text,
          }
          return self.send_request(api_url, params, method='POST')