text: import os
  import sys
  import numpy as np
  
  sys.path.append("../")
  from nadl.core.tensor import Tensor
  
  tensor_fr1 = np.random.randn(5,5).astype('float32')
  tensor_fr2 = np.random.randn(5,3).astype('float32')
  
  t1 = Tensor(data=tensor_fr1)
  t2 = Tensor(data=tensor_fr2)
  
  out = t1.matmul(t2)
  out.backward()
  
  # print(t1.data, t2.data)