No module named 'torch.nn.functional'

I have python file with lines:

import argparse
import torch
import torch.nn as nn
import torch.nn.functional as F
import torch.optim as optim
from torchvision import datasets, transforms
from torch.autograd import Variable

It generates errors:

  File "C:\gdrive\python\a.py", line 5, in <module>
import torch.nn.functional as F
ModuleNotFoundError: No module named 'torch.nn.functional'

How to fix that error?

I have installed pytorch by using command:

conda install pytorch-cpu torchvision-cpu -c pytorch