Added function to ping a host

Lib/site-packages/pip/_vendor/tenacity/tornadoweb.py

@@ -0,0 +1,59 @@
+# Copyright 2017 Elisey Zanko
+#
+# 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 sys
+import typing
+
+from pip._vendor.tenacity import BaseRetrying
+from pip._vendor.tenacity import DoAttempt
+from pip._vendor.tenacity import DoSleep
+from pip._vendor.tenacity import RetryCallState
+
+from tornado import gen
+
+if typing.TYPE_CHECKING:
+    from tornado.concurrent import Future
+
+_RetValT = typing.TypeVar("_RetValT")
+
+
+class TornadoRetrying(BaseRetrying):
+    def __init__(self, sleep: "typing.Callable[[float], Future[None]]" = gen.sleep, **kwargs: typing.Any) -> None:
+        super().__init__(**kwargs)
+        self.sleep = sleep
+
+    @gen.coroutine  # type: ignore[misc]
+    def __call__(
+        self,
+        fn: "typing.Callable[..., typing.Union[typing.Generator[typing.Any, typing.Any, _RetValT], Future[_RetValT]]]",
+        *args: typing.Any,
+        **kwargs: typing.Any,
+    ) -> "typing.Generator[typing.Any, typing.Any, _RetValT]":
+        self.begin()
+
+        retry_state = RetryCallState(retry_object=self, fn=fn, args=args, kwargs=kwargs)
+        while True:
+            do = self.iter(retry_state=retry_state)
+            if isinstance(do, DoAttempt):
+                try:
+                    result = yield fn(*args, **kwargs)
+                except BaseException:  # noqa: B902
+                    retry_state.set_exception(sys.exc_info())  # type: ignore[arg-type]
+                else:
+                    retry_state.set_result(result)
+            elif isinstance(do, DoSleep):
+                retry_state.prepare_for_next_attempt()
+                yield self.sleep(do)
+            else:
+                raise gen.Return(do)