You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: main.go
    path of file: ./repos/gorgonia/examples/convnet_cuda
    
    the code of the file until where you have to start completion: // +build cuda

package main

import (
	"flag"
	"fmt"
	"log"
	"math/rand"
	"os"
	"os/signal"
	"runtime/pprof"
	"syscall"

	"net/http"
	_ "net/http/pprof"

	"github.com/pkg/errors"
	G "gorgonia.org/gorgonia"
	"gorgonia.org/gorgonia/examples/mnist"
	nnops "gorgonia.org/gorgonia/ops/nn"
	"gorgonia.org/tensor"

	"time"

	pb "gopkg.in/cheggaaa/pb.v1"
)

var (
	epochs     = flag.Int("epochs", 10, "Number of epochs to train for")
	dataset    = flag.String("dataset", "train", "Which dataset to train on? Valid options are \"train\" or \"test\"")
	dtype      = flag.String("dtype", "
    
func newConvNet(g *G.ExprGraph) *convnet {
	w0 := G.NewTensor(g, dt, 4, G.WithShape(32, 1, 3, 3), G.WithName("w0"), G.WithInit(G.GlorotN(1.0)))
	w1 := G.NewTensor(g, dt, 4, G.WithShape(64, 32, 3, 3), G.WithName("w1"), G.WithInit(G.GlorotN(1.0)))
	w2 := G.NewTensor(g, dt, 4, G.WithShape(128, 64, 3, 3), G.WithName("w2"), G.WithInit(G.GlorotN(1.0)))
	w3 := G.NewMatrix(g, dt, G.WithShape(128*3*3, 625), G.WithName("w3"), G.WithInit(G.GlorotN(1.0)))
	w4 := G.NewMatrix(g, dt, G.WithShape(625, 10), G.WithName("w4"), G.WithInit(G.GlorotN(1.0)))
	return &convnet{
		g:  g,
		w0: w0,
		w1: w1,
		w2: w2,
		w3: w3,
		w4: w4,

		d0: 0.2,
		d1: 0.2,
		d2: 0.2,
		d3: 0.55,
	}
}