docs: def get(self, server):
          """
          Returns ServerConfig instance with configuration given server.
  
          :raises ServerConfigConflictError:
              if configuration directory contains configuration for same server
              multiple times
  
          :raises ServerConfigMissingUrlError: if URL is not specified in the configuration
  
          :raises ServerConfigNotFoundError: if configuration for given server is not found
          """
          server_config = self.config.get(server)
          try:
              while server_config is None:
                  new_config = self._read_next_config()
                  server_config = new_config.get(server)
                  new_config.update(self.config)
                  self.config = new_config
          except StopIteration:
              return _default_server_configuration(server)
  
          if CONFIG_URL_KEY_NAME not in server_config:
              message = "'%s' must be specified in configuration for '%s'" \
                  % (CONFIG_URL_KEY_NAME, server)
              raise ServerConfigMissingUrlError(message)
  
          return ServerConfig(server_config)