fix minor comments

follow up

mindspore/ccsrc/minddata/dataset/kernels/compose_op.cc

 /**
- * Copyright 2019 Huawei Technologies Co., Ltd
+ * Copyright 2020 Huawei Technologies Co., Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,7 +18,6 @@
 #include <vector>
 
 #include "minddata/dataset/core/tensor.h"
-#include "minddata/dataset/kernels/py_func_op.h"
 #include "minddata/dataset/kernels/tensor_op.h"
 #include "minddata/dataset/util/status.h"
 

mindspore/ccsrc/minddata/dataset/kernels/image/random_select_subpolicy_op.cc

 /**
- * Copyright 2019 Huawei Technologies Co., Ltd
+ * Copyright 2020 Huawei Technologies Co., Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.

mindspore/ccsrc/minddata/dataset/kernels/random_apply_op.cc

 /**
- * Copyright 2019 Huawei Technologies Co., Ltd
+ * Copyright 2020 Huawei Technologies Co., Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.

mindspore/ccsrc/minddata/dataset/kernels/random_choice_op.cc

 /**
- * Copyright 2019 Huawei Technologies Co., Ltd
+ * Copyright 2020 Huawei Technologies Co., Ltd
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.

mindspore/ccsrc/minddata/dataset/text/kernels/lookup_op.cc

@@ -26,7 +26,7 @@ LookupOp::LookupOp(std::shared_ptr<Vocab> vocab, WordIdType default_id)
 Status LookupOp::Compute(const std::shared_ptr<Tensor> &input, std::shared_ptr<Tensor> *output) {
   IO_CHECK(input, output);
   RETURN_UNEXPECTED_IF_NULL(vocab_);
-  CHECK_FAIL_RETURN_UNEXPECTED(input->type() == DataType::DE_STRING, "None String Tensor.");
+  CHECK_FAIL_RETURN_UNEXPECTED(input->type() == DataType::DE_STRING, "None string tensor received.");
   std::vector<WordIdType> word_ids;
   word_ids.reserve(input->Size());
   for (auto itr = input->begin<std::string_view>(); itr != input->end<std::string_view>(); itr++) {
@@ -34,7 +34,7 @@ Status LookupOp::Compute(const std::shared_ptr<Tensor> &input, std::shared_ptr<T
     word_ids.emplace_back(word_id == Vocab::kNoTokenExists ? default_id_ : word_id);
     CHECK_FAIL_RETURN_UNEXPECTED(
       word_ids.back() != Vocab::kNoTokenExists,
-      "Lookup Error: token" + std::string(*itr) + "doesn't exist in vocab and no unknown token is specified.");
+      "Lookup Error: token: " + std::string(*itr) + " doesn't exist in vocab and no unknown token is specified.");
   }
 
   RETURN_IF_NOT_OK(Tensor::CreateTensor(output, TensorImpl::kFlexible, input->shape(), type_,
@@ -42,8 +42,8 @@ Status LookupOp::Compute(const std::shared_ptr<Tensor> &input, std::shared_ptr<T
   return Status::OK();
 }
 Status LookupOp::OutputType(const std::vector<DataType> &inputs, std::vector<DataType> &outputs) {
-  CHECK_FAIL_RETURN_UNEXPECTED(inputs.size() == NumInput() && outputs.size() == NumOutput(), "size doesn't match");
-  CHECK_FAIL_RETURN_UNEXPECTED(inputs[0] == DataType::DE_STRING, "None String tensor type");
+  CHECK_FAIL_RETURN_UNEXPECTED(inputs.size() == NumInput() && outputs.size() == NumOutput(), "size doesn't match.");
+  CHECK_FAIL_RETURN_UNEXPECTED(inputs[0] == DataType::DE_STRING, "None String tensor type.");
   outputs[0] = type_;
   return Status::OK();
 }