“4558807c48035ee1d279d16975d6e2c607cb35f5”上不存在“paddle/utils/string/to_string_test.cc”
* Expose paddle.framework by pybind11
* Export paddle.framework.{Scope, Variable} to paddle.v2.framework.core.
* See python/paddle/v2/framework/tests/test_scope.py for Python usage
* See paddle/pybind/pybind.cc for C++ bind code.
* add copyright