TypeError: conv2d(): argument 'input' (position 1) must be Tensor, not numpy.ndarray

/usr/local/lib/python3.6/dist-packages/torch/nn/modules/conv.py in forward(self, input) 
318 def forward(self, input): 
319 return F.conv2d(input, self.weight, self.bias, self.stride, --> 
320 self.padding, self.dilation, self.groups)
 
TypeError: conv2d(): argument 'input' (position 1) must be Tensor, not numpy.ndarray