Cherry-pick #23907 & #24223 (#24465)

* remove print statement to make code clean(#23907)
* Try to fix UT Random Fail (#24223)

Author: hutuxian

paddle/fluid/framework/CMakeLists.txt

@@ -157,7 +157,7 @@ if(WITH_PYTHON)
 #Generate an empty \
     #__init__.py to make framework_py_proto as a valid python module.
   add_custom_target(framework_py_proto_init ALL COMMAND ${CMAKE_COMMAND} -E touch __init__.py)
-  add_dependencies(framework_py_proto framework_py_proto_init)
+  add_dependencies(framework_py_proto framework_py_proto_init trainer_py_proto)
   if (NOT WIN32)
     add_custom_command(TARGET framework_py_proto POST_BUILD
       COMMAND ${CMAKE_COMMAND} -E make_directory ${PADDLE_BINARY_DIR}/python/paddle/fluid/proto

python/paddle/fluid/trainer_desc.py

@@ -33,15 +33,11 @@ def __init__(self):
         # Workaround for relative import in protobuf under python3
         # TODO: should be fixed
         cur_path = os.path.dirname(__file__)
-        sys.path.append(cur_path)
-        sys.path.append(cur_path + "/proto")
-
-        # Just for fix random UT fail, will be deleted soon
-        print("cur_path: ", cur_path)
-        print("sys.path: ", sys.path)
-        if os.path.isdir(cur_path + "/proto"):
-            print("[listdir]")
-            print(os.listdir(cur_path + "/proto"))
+        if cur_path not in sys.path:
+            sys.path.append(cur_path)
+        if cur_path + "/proto" not in sys.path:
+            sys.path.append(cur_path + "/proto")
+
         from proto import trainer_desc_pb2
         self.proto_desc = trainer_desc_pb2.TrainerDesc()
         import multiprocessing as mp