message: Windows: Use cc_import to import python lib properly
  Previously, we put python.lib in data attribute of a cc_library and
  manually added the link option. That caused the build to be
  non-hermetic. This change fixed the problem.
diff: @@ -2,20 +2,26 @@ licenses(["restricted"])
  package(default_visibility = ["//visibility:public"])
  +# To build Python C/C++ extension on Windows, we need to link to python import library pythonXY.lib
  +# See https://docs.python.org/3/extending/windows.html
  +cc_import(
  + name = "python_lib",
  + interface_library = select({
  + ":windows": ":python_import_lib",
  + # A placeholder for Unix platforms which makes --no_build happy.
  + "//conditions:default": "not-existing.lib",
  + }),
  + system_provided = 1,
  +)
  +
  cc_library(
  name = "python_headers",
  hdrs = [":python_include"],
  - data = select({
  - ":windows": [":python_import_lib"],
  + deps = select({
  + ":windows": [":python_lib"],
  "//conditions:default": [],
  }),
  includes = ["python_include"],
  - linkopts = select({
  - # TODO(pcloudy): Ideally, this should just go into deps after resolving
  - # https://github.com/bazelbuild/bazel/issues/3237,
  - ":windows": ["$(locations :python_import_lib)"],
  - "//conditions:default": [],
  - }),
  )
  cc_library(
  