arguments are assigned to the named local variables in function body see the calls section for the rules governing this assignment syntacticallyany expression can be used to represent an argumentthe evaluated value is assigned to the local variable see also the parameter glossary entrythe faq question on the difference between arguments and parametersand pep asynchronous context manager an object which controls the environment seen in an async with statement by defining __aenter__(and __aexit__(methods introduced by pep asynchronous generator function which returns an asynchronous generator iterator it looks like coroutine function defined with async def except that it contains yield expressions for producing series of values usable in an async for loop usually refers to asynchronous generator functionbut may refer to an asynchronous generator iterator in some contexts in cases where the intended meaning isn' clearusing the full terms avoids ambiguity an asynchronous generator function may contain await expressions as well as async forand async with statements asynchronous generator iterator an object created by asynchronous generator function this is an asynchronous iterator which when called using the __anext__(method returns an awaitable object which will execute that the body of the asynchronous generator function until the next yield expression each yield temporarily suspends processingremembering the location execution state (including local variables and pending try-statementswhen the asynchronous generator iterator effectively resumes with another awaitable returned by __anext__()it picks up where it left off see pep and pep asynchronous iterable an objectthat can be used in an async for statement must return an asynchronous iterator from its __aiter__(method introduced by pep asynchronous iterator an object that implements the __aiter__(and __anext__(methods __anext__ must return an awaitable object async for resolves the awaitables returned by an asynchronous iterator' __anext__(method until it raises stopasynciteration exception introduced by pep attribute value associated with an object which is referenced by name using dotted expressions for exampleif an object has an attribute it would be referenced as awaitable an object that can be used in an await expression can be coroutine or an object with an __await__(method see also pep bdfl benevolent dictator for lifea guido van rossumpython' creator binary file file object able to read and write bytes-like objects examples of binary files are files opened in binary mode ('rb''wbor 'rb+')sys stdin buffersys stdout bufferand instances of io bytesio and gzip gzipfile see also text file for file object able to read and write str objects bytes-like object an object that supports the bufferobjects and can export -contiguous buffer this includes all bytesbytearrayand array array objectsas well as many common memoryview objects bytes-like objects can be used for various operations that work with binary datathese include compressionsaving to binary fileand sending over socket some operations need the binary data to be mutable the documentation often refers to these as "readwrite bytes-like objectsexample mutable buffer objects include bytearray and memoryview of bytearray other operations require the binary data to be stored in immutable objects ("read-only bytes-like objects")examples of these include bytes and memoryview of bytes object appendix glossary