oss ydb: fix dstool building and test run

1 files changed, 46 insertions, 0 deletions

diff --git a/contrib/deprecated/python/backports-abc/README.rst b/contrib/deprecated/python/backports-abc/README.rst
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+=============
+ABC-Backports
+=============
+
+Usage:
+
+.. code-block:: python
+
+    try:
+        # ABCs live in "collections.abc" in Python >= 3.3
+        from collections.abc import Coroutine, Generator
+    except ImportError:
+        # fall back to import from "backports_abc"
+        from backports_abc import Coroutine, Generator
+
+You can also install the ABCs into the stdlib by calling the ``patch()``
+function:
+
+.. code-block:: python
+
+    import backports_abc
+    backports_abc.patch()
+
+    try:
+        # ABCs live in "collections.abc" in Python >= 3.3
+        from collections.abc import Coroutine, Generator
+    except ImportError:
+        # fall back to import from "collections" in Python <= 3.2
+        from backports_abc import Coroutine, Generator
+
+Currently, ``patch()`` provides the following names if missing:
+
+* ``collections.abc.Generator``
+* ``collections.abc.Awaitable``
+* ``collections.abc.Coroutine``
+* ``inspect.isawaitable(obj)``
+
+All of them are also available directly from the ``backports_abc``
+module namespace.
+
+In Python 2.x and Python 3.2, it patches the ``collections`` module
+instead of the ``collections.abc`` module.  Any names that are already
+available when importing this module will not be overwritten.
+
+The names that were previously patched by ``patch()`` can be queried
+through the mapping in ``backports_abc.PATCHED``.