Remove Python 2 configuration and targets

Bazel is dropping support for Python 2

Work towards bazelbuild/bazel#17293

examples/third_party/python/BUILD.bazel

@@ -2,19 +2,11 @@ load("@rules_python//python:defs.bzl", "py_runtime", "py_runtime_pair", "py_test
 
 exports_files(
     [
-        "BUILD.python2.bazel",
         "BUILD.python3.bazel",
     ],
     visibility = ["//visibility:public"],
 )
 
-py_runtime(
-    name = "py2_runtime",
-    files = ["@python2"],
-    interpreter = "@python2//:python2_bin",
-    python_version = "PY2",
-)
-
 py_runtime(
     name = "py3_runtime",
     files = ["@python3"],
@@ -24,7 +16,6 @@ py_runtime(
 
 py_runtime_pair(
     name = "py_runtime_pair",
-    py2_runtime = ":py2_runtime",
     py3_runtime = ":py3_runtime",
 )
 
@@ -34,13 +25,6 @@ toolchain(
     toolchain_type = "@rules_python//python:toolchain_type",
 )
 
-py_test(
-    name = "python2_test",
-    srcs = ["python2_test.py"],
-    python_version = "PY2",
-    visibility = ["//:__pkg__"],
-)
-
 py_test(
     name = "python3_test",
     srcs = ["python3_test.py"],
@@ -51,7 +35,6 @@ py_test(
 test_suite(
     name = "python_tests",
     tests = [
-        ":python2_test",
         ":python3_test",
     ],
 )

examples/third_party/python/python_repositories.bzl

@@ -5,16 +5,6 @@ load("@bazel_tools//tools/build_defs/repo:utils.bzl", "maybe")
 
 # buildifier: disable=unnamed-macro
 def python_repositories():
-    maybe(
-        http_archive,
-        name = "python2",
-        build_file = Label("//python:BUILD.python2.bazel"),
-        strip_prefix = "Python-2.7.18",
-        urls = [
-            "https://www.python.org/ftp/python/2.7.18/Python-2.7.18.tgz",
-        ],
-        sha256 = "da3080e3b488f648a3d7a4560ddee895284c3380b11d6de75edb986526b9a814",
-    )
     maybe(
         http_archive,
         name = "python3",