def prepare_request(command, extension = nil)
      cmd = EPP::Requests::Command.new(req_tid, command, extension)
      EPP::Request.new(cmd)
    end
def prepare_request(command, extension = nil)
      cmd = EPP::Requests::Command.new(req_tid, command, extension)
      EPP::Request.new(cmd)
    end
Send request to server

 @overload request(command, payload)
   @param [String, #to_s] command EPP Command to call
   @param [XML::Node, XML::Document, String] payload EPP XML Payload
 @overload request(command)
   @param [String, #to_s] command EPP Command to call
   @yield [xml] block to construct payload
   @yieldparam [XML::Node] xml XML Node of the command
     for the payload to be added into
 @return [Response] EPP Response object
 def request(command, payload = nil, extension = nil, &block)
   @req = if payload.nil? && block_given?
     Request.new(command, req_tid, &block)
   else
     Request.new(command, payload, extension, req_tid)
   end

   @resp = send_recv_frame(@req)
 end
 @note Primarily an internal method, exposed to enable testing
 @param [] command
 @param [] extension
 @return [EPP::Request]
 @see request