docs: def find_ostype(ost_id=None, ost_name=None, ost_arch=None):
          """
          find the OS type (ost) according ost id (prioritary) or ost name
          :param ost_id: the OS type id
          :param ost_name: the OS type name
          :param ost_arch: the OS type architecture
          :return: found OS type or None if not found
          """
          LOGGER.debug("OSTypeService.find_ostype")
          if (ost_id is None or not ost_id) and (ost_name is None or not ost_name) and (ost_arch is None or not ost_arch):
              raise exceptions.ArianeCallParametersError('id and (name, architecture)')
  
          if (ost_id is not None and ost_id) and ((ost_name is not None and ost_name) or
                                                  (ost_arch is not None and ost_arch)):
              LOGGER.warn('OSTypeService.find_ostype - Both id and (name, arc) are defined. Will give you search on id.')
              ost_name = None
              ost_arch = None
  
          if ((ost_name is not None and ost_name) and (ost_arch is None or not ost_arch)) or\
             ((ost_arch is not None and ost_arch) and (ost_name is None or not ost_name)):
              raise exceptions.ArianeCallParametersError('(name, architecture)')
  
          params = None
          if ost_id is not None and ost_id:
              params = {'id': ost_id}
          elif ost_name is not None and ost_name and ost_arch is not None and ost_arch:
              params = {'name': ost_name, 'arc': ost_arch}
  
          ret = None
          if params is not None:
              args = {'http_operation': 'GET', 'operation_path': 'get', 'parameters': params}
              response = OSTypeService.requester.call(args)
              if response.rc == 0:
                  ret = OSType.json_2_ostype(response.response_content)
              elif response.rc != 404:
                  err_msg = 'OSTypeService.find_ostype - Problem while finding OS Type (id:' + str(ost_id) + \
                            ', name:' + str(ost_name) + '). ' + \
                            'Reason: ' + str(response.response_content) + '-' + str(response.error_message) + \
                            " (" + str(response.rc) + ")"
                  LOGGER.warning(
                      err_msg
                  )
  
          return ret