Bazel python runtime

• py_runtime definition
• starlark rule

Using python_top

Execution via starlark action

bazel build --python_top=//tools/python:py3_windows_runtime //:test

Running as target

bazel run --python_top=//tools/python:py3_windows_runtime //tools/generator -- "C:\temp\my_testfile"

Using python toolchain

Requieres bazel >= 0.25.0

Execution via starlark action

bazel build --incompatible_use_python_toolchains //:test

Running as target

bazel run --incompatible_use_python_toolchains //tools/generator -- "C:\temp\my_testfile"