address code review: change atol

Author: Hao Jin

tests/python/unittest/test_operator.py

@@ -2419,7 +2419,7 @@ def check_l2_normalization(in_shape, mode, dtype, norm_eps=1e-10):
     exe = out.simple_bind(ctx=ctx, data=in_data.shape)
     output = exe.forward(is_train=True, data=in_data)
     # compare numpy + mxnet
-    assert_almost_equal(exe.outputs[0].asnumpy(), np_out, rtol=1e-2 if dtype is 'float16' else 1e-5, atol=1e-20)
+    assert_almost_equal(exe.outputs[0].asnumpy(), np_out, rtol=1e-2 if dtype is 'float16' else 1e-5, atol=1e-5)
     # check gradient
     check_numeric_gradient(out, [in_data], numeric_eps=1e-3, rtol=1e-2, atol=1e-3)