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venv/lib/python3.9/site-packages/graphql/pyutils/is_awaitable.py

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+import inspect
+from typing import Any
+from types import CoroutineType, GeneratorType
+
+__all__ = ["is_awaitable"]
+
+CO_ITERABLE_COROUTINE = inspect.CO_ITERABLE_COROUTINE
+
+
+def is_awaitable(value: Any) -> bool:
+    """Return true if object can be passed to an ``await`` expression.
+
+    Instead of testing if the object is an instance of abc.Awaitable, it checks
+    the existence of an `__await__` attribute. This is much faster.
+    """
+    return (
+        # check for coroutine objects
+        isinstance(value, CoroutineType)
+        # check for old-style generator based coroutine objects
+        or isinstance(value, GeneratorType)
+        and bool(value.gi_code.co_flags & CO_ITERABLE_COROUTINE)
+        # check for other awaitables (e.g. futures)
+        or hasattr(value, "__await__")
+    )