docs: def __create_xml_request(self, text):
          """ make xml content from given text """
          # create base stucture
          soap_root = ET.Element('soap:Envelope', {
              'xmlns:xsi': 'http://www.w3.org/2001/XMLSchema-instance',
              'xmlns:xsd': 'http://www.w3.org/2001/XMLSchema',
              'xmlns:soap': 'http://schemas.xmlsoap.org/soap/envelope/', })
          body = ET.SubElement(soap_root, 'soap:Body')
          process_text = ET.SubElement(body, 'ProcessText', {
              'xmlns': 'http://typograf.artlebedev.ru/webservices/', })
          # add contents
          ET.SubElement(process_text, 'text').text = text
          ET.SubElement(process_text, 'entityType').text = str(self._entityType)
          ET.SubElement(process_text, 'useBr').text = str(self._useBr)
          ET.SubElement(process_text, 'useP').text = str(self._useP)
          ET.SubElement(process_text, 'maxNobr').text = str(self._maxNobr)
          # create tree and write it
          string = Container()
          soap = ET.ElementTree(soap_root)
          soap.write(string, encoding=self._encoding, xml_declaration=True)
          if PY3:
              return string.getvalue().decode(self._encoding)
          return string.getvalue()