FM / python3.7

/opt/alt/python37/lib64/python3.7

Name	Size	Mode	Actions
asyncio/	-	0755	rm
collections/	-	0755	rm
concurrent/	-	0755	rm
config-3.7m/	-	0755	rm
ctypes/	-	0755	rm
curses/	-	0755	rm
dbm/	-	0755	rm
distutils/	-	0755	rm
email/	-	0755	rm
encodings/	-	0755	rm
ensurepip/	-	0755	rm
html/	-	0755	rm
http/	-	0755	rm
idlelib/	-	0755	rm
importlib/	-	0755	rm
json/	-	0755	rm
lib-dynload/	-	0755	rm
lib2to3/	-	0755	rm
logging/	-	0755	rm
multiprocessing/	-	0755	rm
pydoc_data/	-	0755	rm
site-packages/	-	0755	rm
sqlite3/	-	0755	rm
test/	-	0755	rm
unittest/	-	0755	rm
urllib/	-	0755	rm
venv/	-	0755	rm
wsgiref/	-	0755	rm
xml/	-	0755	rm
xmlrpc/	-	0755	rm
__pycache__/	-	0755	rm
abc.py	5580	0644	edit dl rm
aifc.py	32814	0644	edit dl rm
antigravity.py	477	0644	edit dl rm
argparse.py	95372	0644	edit dl rm
ast.py	12842	0644	edit dl rm
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asyncore.py	20118	0644	edit dl rm
base64.py	20393	0755	edit dl rm
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binhex.py	13954	0644	edit dl rm
bisect.py	2557	0644	edit dl rm
bz2.py	12410	0644	edit dl rm
calendar.py	24826	0644	edit dl rm
cgi.py	35050	0755	edit dl rm
cgitb.py	12018	0644	edit dl rm
chunk.py	5435	0644	edit dl rm
cmd.py	14860	0644	edit dl rm
code.py	10622	0644	edit dl rm
codecs.py	36615	0644	edit dl rm
codeop.py	6275	0644	edit dl rm
colorsys.py	4064	0644	edit dl rm
compileall.py	13788	0644	edit dl rm
configparser.py	54283	0644	edit dl rm
contextlib.py	24763	0644	edit dl rm
contextvars.py	129	0644	edit dl rm
copy.py	8856	0644	edit dl rm
copyreg.py	7017	0644	edit dl rm
cProfile.py	6253	0755	edit dl rm
crypt.py	3346	0644	edit dl rm
csv.py	16180	0644	edit dl rm
dataclasses.py	49520	0644	edit dl rm
datetime.py	86544	0644	edit dl rm
decimal.py	320	0644	edit dl rm
difflib.py	84393	0644	edit dl rm
dis.py	19888	0644	edit dl rm
doctest.py	104560	0644	edit dl rm
dummy_threading.py	2815	0644	edit dl rm
enum.py	35043	0644	edit dl rm
filecmp.py	9830	0644	edit dl rm
fileinput.py	14625	0644	edit dl rm
fnmatch.py	4056	0644	edit dl rm
formatter.py	15143	0644	edit dl rm
fractions.py	23752	0644	edit dl rm
ftplib.py	35618	0644	edit dl rm
functools.py	32932	0644	edit dl rm
genericpath.py	4912	0644	edit dl rm
getopt.py	7489	0644	edit dl rm
getpass.py	5994	0644	edit dl rm
gettext.py	21967	0644	edit dl rm
glob.py	5638	0644	edit dl rm
gzip.py	20637	0644	edit dl rm
hashlib.py	9534	0644	edit dl rm
heapq.py	23017	0644	edit dl rm
hmac.py	6517	0644	edit dl rm
imaplib.py	53292	0644	edit dl rm
imghdr.py	3795	0644	edit dl rm
imp.py	10536	0644	edit dl rm
inspect.py	117635	0644	edit dl rm
io.py	3517	0644	edit dl rm
ipaddress.py	73578	0644	edit dl rm
keyword.py	2256	0755	edit dl rm
linecache.py	5330	0644	edit dl rm
locale.py	78191	0644	edit dl rm
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opcode.py	5824	0644	edit dl rm
operator.py	10863	0644	edit dl rm
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os.py	37901	0644	edit dl rm
pathlib.py	50329	0644	edit dl rm
pdb.py	62505	0755	edit dl rm
pickle.py	57994	0644	edit dl rm
pickletools.py	91220	0644	edit dl rm
pipes.py	8916	0644	edit dl rm
pkgutil.py	21461	0644	edit dl rm
platform.py	46994	0755	edit dl rm
plistlib.py	30709	0644	edit dl rm
poplib.py	14964	0644	edit dl rm
posixpath.py	15771	0644	edit dl rm
pprint.py	20884	0644	edit dl rm
profile.py	22494	0755	edit dl rm
pstats.py	27315	0644	edit dl rm
pty.py	4763	0644	edit dl rm
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pydoc.py	105876	0644	edit dl rm
py_compile.py	8001	0644	edit dl rm
queue.py	11359	0644	edit dl rm
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random.py	27557	0644	edit dl rm
re.py	15306	0644	edit dl rm
reprlib.py	5267	0644	edit dl rm
rlcompleter.py	7097	0644	edit dl rm
runpy.py	11959	0644	edit dl rm
sched.py	6442	0644	edit dl rm
secrets.py	2038	0644	edit dl rm
selectors.py	18561	0644	edit dl rm
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site.py	21575	0644	edit dl rm
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socket.py	27469	0644	edit dl rm
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ssl.py	45495	0644	edit dl rm
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string.py	11564	0644	edit dl rm
stringprep.py	12917	0644	edit dl rm
struct.py	257	0644	edit dl rm
subprocess.py	72649	0644	edit dl rm
sunau.py	18375	0644	edit dl rm
symbol.py	2142	0755	edit dl rm
symtable.py	7279	0644	edit dl rm
sysconfig.py	24440	0644	edit dl rm
tabnanny.py	11419	0755	edit dl rm
tarfile.py	92675	0755	edit dl rm
telnetlib.py	23135	0644	edit dl rm
tempfile.py	26730	0644	edit dl rm
textwrap.py	19407	0644	edit dl rm
this.py	1003	0644	edit dl rm
threading.py	49284	0644	edit dl rm
timeit.py	13493	0755	edit dl rm
token.py	3763	0644	edit dl rm
tokenize.py	27031	0644	edit dl rm
trace.py	28903	0755	edit dl rm
traceback.py	23437	0644	edit dl rm
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tty.py	879	0644	edit dl rm
types.py	9897	0644	edit dl rm
typing.py	56438	0644	edit dl rm
uu.py	7277	0644	edit dl rm
uuid.py	29518	0644	edit dl rm
warnings.py	20080	0644	edit dl rm
wave.py	18230	0644	edit dl rm
weakref.py	21508	0644	edit dl rm
webbrowser.py	23715	0755	edit dl rm
xdrlib.py	5913	0644	edit dl rm
zipapp.py	7535	0644	edit dl rm
zipfile.py	81094	0644	edit dl rm
_bootlocale.py	1801	0644	edit dl rm
_collections_abc.py	26424	0644	edit dl rm
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_compression.py	5340	0644	edit dl rm
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_weakrefset.py	5679	0644	edit dl rm
__future__.py	5101	0644	edit dl rm
__phello__.foo.py	64	0644	edit dl rm

Edit: /opt/alt/python37/lib64/python3.7/contextlib.py (24763B)

"""Utilities for with-statement contexts.  See PEP 343."""
import abc
import sys
import _collections_abc
from collections import deque
from functools import wraps

__all__ = ["asynccontextmanager", "contextmanager", "closing", "nullcontext",
           "AbstractContextManager", "AbstractAsyncContextManager",
           "AsyncExitStack", "ContextDecorator", "ExitStack",
           "redirect_stdout", "redirect_stderr", "suppress"]

class AbstractContextManager(abc.ABC):

"""An abstract base class for context managers."""

def __enter__(self):
        """Return `self` upon entering the runtime context."""
        return self

@abc.abstractmethod
    def __exit__(self, exc_type, exc_value, traceback):
        """Raise any exception triggered within the runtime context."""
        return None

@classmethod
    def __subclasshook__(cls, C):
        if cls is AbstractContextManager:
            return _collections_abc._check_methods(C, "__enter__", "__exit__")
        return NotImplemented

class AbstractAsyncContextManager(abc.ABC):

"""An abstract base class for asynchronous context managers."""

async def __aenter__(self):
        """Return `self` upon entering the runtime context."""
        return self

@abc.abstractmethod
    async def __aexit__(self, exc_type, exc_value, traceback):
        """Raise any exception triggered within the runtime context."""
        return None

@classmethod
    def __subclasshook__(cls, C):
        if cls is AbstractAsyncContextManager:
            return _collections_abc._check_methods(C, "__aenter__",
                                                   "__aexit__")
        return NotImplemented

class ContextDecorator(object):
    "A base class or mixin that enables context managers to work as decorators."

def _recreate_cm(self):
        """Return a recreated instance of self.

Allows an otherwise one-shot context manager like
        _GeneratorContextManager to support use as
        a decorator via implicit recreation.

This is a private interface just for _GeneratorContextManager.
        See issue #11647 for details.
        """
        return self

def __call__(self, func):
        @wraps(func)
        def inner(*args, **kwds):
            with self._recreate_cm():
                return func(*args, **kwds)
        return inner

class _GeneratorContextManagerBase:
    """Shared functionality for @contextmanager and @asynccontextmanager."""

def __init__(self, func, args, kwds):
        self.gen = func(*args, **kwds)
        self.func, self.args, self.kwds = func, args, kwds
        # Issue 19330: ensure context manager instances have good docstrings
        doc = getattr(func, "__doc__", None)
        if doc is None:
            doc = type(self).__doc__
        self.__doc__ = doc
        # Unfortunately, this still doesn't provide good help output when
        # inspecting the created context manager instances, since pydoc
        # currently bypasses the instance docstring and shows the docstring
        # for the class instead.
        # See http://bugs.python.org/issue19404 for more details.

class _GeneratorContextManager(_GeneratorContextManagerBase,
                               AbstractContextManager,
                               ContextDecorator):
    """Helper for @contextmanager decorator."""

def _recreate_cm(self):
        # _GCM instances are one-shot context managers, so the
        # CM must be recreated each time a decorated function is
        # called
        return self.__class__(self.func, self.args, self.kwds)

def __enter__(self):
        # do not keep args and kwds alive unnecessarily
        # they are only needed for recreation, which is not possible anymore
        del self.args, self.kwds, self.func
        try:
            return next(self.gen)
        except StopIteration:
            raise RuntimeError("generator didn't yield") from None

def __exit__(self, type, value, traceback):
        if type is None:
            try:
                next(self.gen)
            except StopIteration:
                return False
            else:
                raise RuntimeError("generator didn't stop")
        else:
            if value is None:
                # Need to force instantiation so we can reliably
                # tell if we get the same exception back
                value = type()
            try:
                self.gen.throw(type, value, traceback)
            except StopIteration as exc:
                # Suppress StopIteration *unless* it's the same exception that
                # was passed to throw().  This prevents a StopIteration
                # raised inside the "with" statement from being suppressed.
                return exc is not value
            except RuntimeError as exc:
                # Don't re-raise the passed in exception. (issue27122)
                if exc is value:
                    return False
                # Likewise, avoid suppressing if a StopIteration exception
                # was passed to throw() and later wrapped into a RuntimeError
                # (see PEP 479).
                if type is StopIteration and exc.__cause__ is value:
                    return False
                raise
            except:
                # only re-raise if it's *not* the exception that was
                # passed to throw(), because __exit__() must not raise
                # an exception unless __exit__() itself failed.  But throw()
                # has to raise the exception to signal propagation, so this
                # fixes the impedance mismatch between the throw() protocol
                # and the __exit__() protocol.
                #
                # This cannot use 'except BaseException as exc' (as in the
                # async implementation) to maintain compatibility with
                # Python 2, where old-style class exceptions are not caught
                # by 'except BaseException'.
                if sys.exc_info()[1] is value:
                    return False
                raise
            raise RuntimeError("generator didn't stop after throw()")

class _AsyncGeneratorContextManager(_GeneratorContextManagerBase,
                                    AbstractAsyncContextManager):
    """Helper for @asynccontextmanager."""

async def __aenter__(self):
        try:
            return await self.gen.__anext__()
        except StopAsyncIteration:
            raise RuntimeError("generator didn't yield") from None

async def __aexit__(self, typ, value, traceback):
        if typ is None:
            try:
                await self.gen.__anext__()
            except StopAsyncIteration:
                return
            else:
                raise RuntimeError("generator didn't stop")
        else:
            if value is None:
                value = typ()
            # See _GeneratorContextManager.__exit__ for comments on subtleties
            # in this implementation
            try:
                await self.gen.athrow(typ, value, traceback)
                raise RuntimeError("generator didn't stop after athrow()")
            except StopAsyncIteration as exc:
                return exc is not value
            except RuntimeError as exc:
                if exc is value:
                    return False
                # Avoid suppressing if a StopIteration exception
                # was passed to throw() and later wrapped into a RuntimeError
                # (see PEP 479 for sync generators; async generators also
                # have this behavior). But do this only if the exception wrapped
                # by the RuntimeError is actully Stop(Async)Iteration (see
                # issue29692).
                if isinstance(value, (StopIteration, StopAsyncIteration)):
                    if exc.__cause__ is value:
                        return False
                raise
            except BaseException as exc:
                if exc is not value:
                    raise

def contextmanager(func):
    """@contextmanager decorator.

Typical usage:

@contextmanager
        def some_generator(<arguments>):
            <setup>
            try:
                yield <value>
            finally:
                <cleanup>

This makes this:

with some_generator(<arguments>) as <variable>:
            <body>

equivalent to this:

<setup>
        try:
            <variable> = <value>
            <body>
        finally:
            <cleanup>
    """
    @wraps(func)
    def helper(*args, **kwds):
        return _GeneratorContextManager(func, args, kwds)
    return helper

def asynccontextmanager(func):
    """@asynccontextmanager decorator.

Typical usage:

@asynccontextmanager
        async def some_async_generator(<arguments>):
            <setup>
            try:
                yield <value>
            finally:
                <cleanup>

This makes this:

async with some_async_generator(<arguments>) as <variable>:
            <body>

equivalent to this:

<setup>
        try:
            <variable> = <value>
            <body>
        finally:
            <cleanup>
    """
    @wraps(func)
    def helper(*args, **kwds):
        return _AsyncGeneratorContextManager(func, args, kwds)
    return helper

class closing(AbstractContextManager):
    """Context to automatically close something at the end of a block.

Code like this:

with closing(<module>.open(<arguments>)) as f:
            <block>

is equivalent to this:

f = <module>.open(<arguments>)
        try:
            <block>
        finally:
            f.close()

"""
    def __init__(self, thing):
        self.thing = thing
    def __enter__(self):
        return self.thing
    def __exit__(self, *exc_info):
        self.thing.close()

class _RedirectStream(AbstractContextManager):

_stream = None

def __init__(self, new_target):
        self._new_target = new_target
        # We use a list of old targets to make this CM re-entrant
        self._old_targets = []

def __enter__(self):
        self._old_targets.append(getattr(sys, self._stream))
        setattr(sys, self._stream, self._new_target)
        return self._new_target

def __exit__(self, exctype, excinst, exctb):
        setattr(sys, self._stream, self._old_targets.pop())

class redirect_stdout(_RedirectStream):
    """Context manager for temporarily redirecting stdout to another file.

# How to send help() to stderr
        with redirect_stdout(sys.stderr):
            help(dir)

# How to write help() to a file
        with open('help.txt', 'w') as f:
            with redirect_stdout(f):
                help(pow)
    """

_stream = "stdout"

class redirect_stderr(_RedirectStream):
    """Context manager for temporarily redirecting stderr to another file."""

_stream = "stderr"

class suppress(AbstractContextManager):
    """Context manager to suppress specified exceptions

After the exception is suppressed, execution proceeds with the next
    statement following the with statement.

with suppress(FileNotFoundError):
             os.remove(somefile)
         # Execution still resumes here if the file was already removed
    """

def __init__(self, *exceptions):
        self._exceptions = exceptions

def __enter__(self):
        pass

def __exit__(self, exctype, excinst, exctb):
        # Unlike isinstance and issubclass, CPython exception handling
        # currently only looks at the concrete type hierarchy (ignoring
        # the instance and subclass checking hooks). While Guido considers
        # that a bug rather than a feature, it's a fairly hard one to fix
        # due to various internal implementation details. suppress provides
        # the simpler issubclass based semantics, rather than trying to
        # exactly reproduce the limitations of the CPython interpreter.
        #
        # See http://bugs.python.org/issue12029 for more details
        return exctype is not None and issubclass(exctype, self._exceptions)

class _BaseExitStack:
    """A base class for ExitStack and AsyncExitStack."""

@staticmethod
    def _create_exit_wrapper(cm, cm_exit):
        def _exit_wrapper(exc_type, exc, tb):
            return cm_exit(cm, exc_type, exc, tb)
        return _exit_wrapper

@staticmethod
    def _create_cb_wrapper(*args, **kwds):
        callback, *args = args
        def _exit_wrapper(exc_type, exc, tb):
            callback(*args, **kwds)
        return _exit_wrapper

def __init__(self):
        self._exit_callbacks = deque()

def pop_all(self):
        """Preserve the context stack by transferring it to a new instance."""
        new_stack = type(self)()
        new_stack._exit_callbacks = self._exit_callbacks
        self._exit_callbacks = deque()
        return new_stack

def push(self, exit):
        """Registers a callback with the standard __exit__ method signature.

Can suppress exceptions the same way __exit__ method can.
        Also accepts any object with an __exit__ method (registering a call
        to the method instead of the object itself).
        """
        # We use an unbound method rather than a bound method to follow
        # the standard lookup behaviour for special methods.
        _cb_type = type(exit)

try:
            exit_method = _cb_type.__exit__
        except AttributeError:
            # Not a context manager, so assume it's a callable.
            self._push_exit_callback(exit)
        else:
            self._push_cm_exit(exit, exit_method)
        return exit  # Allow use as a decorator.

def enter_context(self, cm):
        """Enters the supplied context manager.

If successful, also pushes its __exit__ method as a callback and
        returns the result of the __enter__ method.
        """
        # We look up the special methods on the type to match the with
        # statement.
        _cm_type = type(cm)
        _exit = _cm_type.__exit__
        result = _cm_type.__enter__(cm)
        self._push_cm_exit(cm, _exit)
        return result

def callback(*args, **kwds):
        """Registers an arbitrary callback and arguments.

Cannot suppress exceptions.
        """
        if len(args) >= 2:
            self, callback, *args = args
        elif not args:
            raise TypeError("descriptor 'callback' of '_BaseExitStack' object "
                            "needs an argument")
        elif 'callback' in kwds:
            callback = kwds.pop('callback')
            self, *args = args
        else:
            raise TypeError('callback expected at least 1 positional argument, '
                            'got %d' % (len(args)-1))

_exit_wrapper = self._create_cb_wrapper(callback, *args, **kwds)

# We changed the signature, so using @wraps is not appropriate, but
        # setting __wrapped__ may still help with introspection.
        _exit_wrapper.__wrapped__ = callback
        self._push_exit_callback(_exit_wrapper)
        return callback  # Allow use as a decorator

def _push_cm_exit(self, cm, cm_exit):
        """Helper to correctly register callbacks to __exit__ methods."""
        _exit_wrapper = self._create_exit_wrapper(cm, cm_exit)
        _exit_wrapper.__self__ = cm
        self._push_exit_callback(_exit_wrapper, True)

def _push_exit_callback(self, callback, is_sync=True):
        self._exit_callbacks.append((is_sync, callback))

# Inspired by discussions on http://bugs.python.org/issue13585
class ExitStack(_BaseExitStack, AbstractContextManager):
    """Context manager for dynamic management of a stack of exit callbacks.

For example:
        with ExitStack() as stack:
            files = [stack.enter_context(open(fname)) for fname in filenames]
            # All opened files will automatically be closed at the end of
            # the with statement, even if attempts to open files later
            # in the list raise an exception.
    """

def __enter__(self):
        return self

def __exit__(self, *exc_details):
        received_exc = exc_details[0] is not None

# We manipulate the exception state so it behaves as though
        # we were actually nesting multiple with statements
        frame_exc = sys.exc_info()[1]
        def _fix_exception_context(new_exc, old_exc):
            # Context may not be correct, so find the end of the chain
            while 1:
                exc_context = new_exc.__context__
                if exc_context is old_exc:
                    # Context is already set correctly (see issue 20317)
                    return
                if exc_context is None or exc_context is frame_exc:
                    break
                new_exc = exc_context
            # Change the end of the chain to point to the exception
            # we expect it to reference
            new_exc.__context__ = old_exc

# Callbacks are invoked in LIFO order to match the behaviour of
        # nested context managers
        suppressed_exc = False
        pending_raise = False
        while self._exit_callbacks:
            is_sync, cb = self._exit_callbacks.pop()
            assert is_sync
            try:
                if cb(*exc_details):
                    suppressed_exc = True
                    pending_raise = False
                    exc_details = (None, None, None)
            except:
                new_exc_details = sys.exc_info()
                # simulate the stack of exceptions by setting the context
                _fix_exception_context(new_exc_details[1], exc_details[1])
                pending_raise = True
                exc_details = new_exc_details
        if pending_raise:
            try:
                # bare "raise exc_details[1]" replaces our carefully
                # set-up context
                fixed_ctx = exc_details[1].__context__
                raise exc_details[1]
            except BaseException:
                exc_details[1].__context__ = fixed_ctx
                raise
        return received_exc and suppressed_exc

def close(self):
        """Immediately unwind the context stack."""
        self.__exit__(None, None, None)

# Inspired by discussions on https://bugs.python.org/issue29302
class AsyncExitStack(_BaseExitStack, AbstractAsyncContextManager):
    """Async context manager for dynamic management of a stack of exit
    callbacks.

For example:
        async with AsyncExitStack() as stack:
            connections = [await stack.enter_async_context(get_connection())
                for i in range(5)]
            # All opened connections will automatically be released at the
            # end of the async with statement, even if attempts to open a
            # connection later in the list raise an exception.
    """

@staticmethod
    def _create_async_exit_wrapper(cm, cm_exit):
        async def _exit_wrapper(exc_type, exc, tb):
            return await cm_exit(cm, exc_type, exc, tb)
        return _exit_wrapper

@staticmethod
    def _create_async_cb_wrapper(*args, **kwds):
        callback, *args = args
        async def _exit_wrapper(exc_type, exc, tb):
            await callback(*args, **kwds)
        return _exit_wrapper

async def enter_async_context(self, cm):
        """Enters the supplied async context manager.

If successful, also pushes its __aexit__ method as a callback and
        returns the result of the __aenter__ method.
        """
        _cm_type = type(cm)
        _exit = _cm_type.__aexit__
        result = await _cm_type.__aenter__(cm)
        self._push_async_cm_exit(cm, _exit)
        return result

def push_async_exit(self, exit):
        """Registers a coroutine function with the standard __aexit__ method
        signature.

Can suppress exceptions the same way __aexit__ method can.
        Also accepts any object with an __aexit__ method (registering a call
        to the method instead of the object itself).
        """
        _cb_type = type(exit)
        try:
            exit_method = _cb_type.__aexit__
        except AttributeError:
            # Not an async context manager, so assume it's a coroutine function
            self._push_exit_callback(exit, False)
        else:
            self._push_async_cm_exit(exit, exit_method)
        return exit  # Allow use as a decorator

def push_async_callback(*args, **kwds):
        """Registers an arbitrary coroutine function and arguments.

Cannot suppress exceptions.
        """
        if len(args) >= 2:
            self, callback, *args = args
        elif not args:
            raise TypeError("descriptor 'push_async_callback' of "
                            "'AsyncExitStack' object needs an argument")
        elif 'callback' in kwds:
            callback = kwds.pop('callback')
            self, *args = args
        else:
            raise TypeError('push_async_callback expected at least 1 '
                            'positional argument, got %d' % (len(args)-1))

_exit_wrapper = self._create_async_cb_wrapper(callback, *args, **kwds)

# We changed the signature, so using @wraps is not appropriate, but
        # setting __wrapped__ may still help with introspection.
        _exit_wrapper.__wrapped__ = callback
        self._push_exit_callback(_exit_wrapper, False)
        return callback  # Allow use as a decorator

async def aclose(self):
        """Immediately unwind the context stack."""
        await self.__aexit__(None, None, None)

def _push_async_cm_exit(self, cm, cm_exit):
        """Helper to correctly register coroutine function to __aexit__
        method."""
        _exit_wrapper = self._create_async_exit_wrapper(cm, cm_exit)
        _exit_wrapper.__self__ = cm
        self._push_exit_callback(_exit_wrapper, False)

async def __aenter__(self):
        return self

async def __aexit__(self, *exc_details):
        received_exc = exc_details[0] is not None

if cb_suppress:
                    suppressed_exc = True
                    pending_raise = False
                    exc_details = (None, None, None)
            except:
                new_exc_details = sys.exc_info()
                # simulate the stack of exceptions by setting the context
                _fix_exception_context(new_exc_details[1], exc_details[1])
                pending_raise = True
                exc_details = new_exc_details
        if pending_raise:
            try:
                # bare "raise exc_details[1]" replaces our carefully
                # set-up context
                fixed_ctx = exc_details[1].__context__
                raise exc_details[1]
            except BaseException:
                exc_details[1].__context__ = fixed_ctx
                raise
        return received_exc and suppressed_exc

class nullcontext(AbstractContextManager):
    """Context manager that does no additional processing.

Used as a stand-in for a normal context manager, when a particular
    block of code is only sometimes used with a normal context manager:

cm = optional_cm if condition else nullcontext()
    with cm:
        # Perform operation, using optional_cm if condition is True
    """

def __init__(self, enter_result=None):
        self.enter_result = enter_result

def __enter__(self):
        return self.enter_result

def __exit__(self, *excinfo):
        pass

cmd: