text: # Copyright 2019 The gRPC Authors
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import os
  import site
  import sys
  
  _GRPC_BAZEL_RUNTIME_ENV = "GRPC_BAZEL_RUNTIME"
  
  
  # TODO(https://github.com/bazelbuild/bazel/issues/6844) Bazel failed to
  # interpret namespace packages correctly. This monkey patch will force the
  # Python process to parse the .pth file in the sys.path to resolve namespace
  # package in the right place.
  # Analysis in depth: https://github.com/bazelbuild/rules_python/issues/55
  def sys_path_to_site_dir_hack():
      """Add valid sys.path item to site directory to parse the .pth files."""
      # Only run within our Bazel environment
      if not os.environ.get(_GRPC_BAZEL_RUNTIME_ENV):
          return
      items = []
      for item in sys.path:
          if os.path.exists(item):
              # The only difference between sys.path and site-directory is
              # whether the .pth file will be parsed or not. A site-directory
              # will always exist in sys.path, but not another way around.
              items.append(item)
      for item in items:
          site.addsitedir(item)
  