code: def memcpy_htod(self, dest, src):
          
          if isinstance(dest, drv.DeviceAllocation):
              drv.memcpy_htod(dest, src)
          else:
              dest = src
docs: perform a host to device memory copy
  
          :param dest: A GPU memory allocation unit
          :type dest: pycuda.driver.DeviceAllocation
  
          :param src: A numpy array in host memory to store the data
          :type src: numpy.ndarray