fix gpubox error (PaddlePaddle#1006)

* disable pir in all ps mode for Paddle 3.0

* fix gpubox error

tools/static_gpubox_trainer.py

@@ -12,9 +12,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
 import os
 os.environ['FLAGS_enable_pir_api'] = '0'
-from __future__ import print_function
 from utils.static_ps.reader_helper import get_reader, get_example_num, get_file_list, get_word_num
 from utils.static_ps.program_helper import get_model, get_strategy
 from utils.static_ps.common_ps import YamlHelper, is_distributed_env