code: def test_public_assign(self):
      prot = tfe.protocol.Pond()
      tfe.set_protocol(prot)
      x_var = prot.define_public_variable(np.zeros(shape=(2, 2)))
      data = np.ones((2, 2))
      x = tfe.define_constant(data)
      tfe.assign(x_var, x)
      result = x_var.read_value().to_native()
      np.testing.assert_array_equal(result, np.ones([2, 2]))
  
imports: import unittest
  import numpy
  import pytest
  import tensorflow
  import tf_encrypted
  from tf_encrypted.protocol.pond import PondMaskedTensor
  from tf_encrypted.protocol.pond import PondPublicTensor
  from tf_encrypted.tensor import fixed100
  from tf_encrypted.tensor import fixed100_ni
  from tf_encrypted.tensor import int64factory
  from tf_encrypted.tensor import int100factory
  from tf_encrypted.tensor import native_factory
label_desc: Use image node_id 2 for calling the TestPondAssign obj's underlying member method code with example usage: obj.test_public_assign() without return types