[Python-Dev] Re: Method __func__ objects are unpicklable
I believe a lot of people use https://pypi.org/project/cloudpickle/ thanks to its support for pickling functions. On Fri, Jun 10, 2022 at 4:56 AM haael wrote: > > > During some sophisticated pickling I noticed that method `__func__` > objects are unpicklable, because they share the name with the bound > method object itself. > > > ``` > from pickle import dumps > > class A: > @classmethod > def b(cls): > pass > > print(A.b) # > > print(A.b.__func__) # > > dumps(A.b) # works > dumps(A.b.__func__) # breaks > # >Traceback (most recent call last): > # > File "", line 1, in > # >_pickle.PicklingError: Can't pickle : > # >it's not the same object as __main__.A.b > ``` > > > The last call compains that global symbol "A.b" is not the same object > as `A.b.__func__`. > > Everything would work if the `__func__` objects had the suffix > ".__func__" in their qualname. > > Actually setting the qualname of the `__func__` object makes it > picklable, but then the bound method object is unpicklable, as it > inherits the name from the `__func__`. It would be good if they were > separate. > > This is an attempt at emulating the desired behavior: > > > ``` > from pickle import dumps > > class A: > pass > > def c(cls): > pass > > A.c = lambda: c(A) > A.c.__qualname__ = "A.c" > A.c.__name__ = "c" > A.c.__self__ = A > A.c.__func__ = c > A.c.__func__.__qualname__ = "A.c.__func__" > > print(A.c) # > print(A.c.__func__) # > > dumps(A.c) # works > dumps(A.c.__func__) # works > ``` > > > Can we make the `__func__` objects picklable this way? > > > haael > > ___ > Python-Dev mailing list -- python-dev@python.org > To unsubscribe send an email to python-dev-le...@python.org > https://mail.python.org/mailman3/lists/python-dev.python.org/ > Message archived at > https://mail.python.org/archives/list/python-dev@python.org/message/N2J6MVLURTBAB5PJLJG3LO6U4PTPJMU2/ > Code of Conduct: http://python.org/psf/codeofconduct/ > ___ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/NSBJC3266COHPPTNJMLVDHNW4AS7E4QE/ Code of Conduct: http://python.org/psf/codeofconduct/
[Python-Dev] Summary of Python tracker Issues
ACTIVITY SUMMARY (2022-06-03 - 2022-06-10)
Python tracker at https://bugs.python.org/
To view or respond to any of the issues listed below, click on the issue.
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Issues counts and deltas:
open7146 ( +0)
closed 51841 ( +0)
total 58987 ( +0)
Open issues with patches: 2890
Most recent 15 issues with no replies (15)
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#47258: Python 3.10 hang at exit in drop_gil() (due to resource warnin
https://bugs.python.org/issue47258
#47256: re: limit the maximum capturing group to 1,073,741,823, reduce
https://bugs.python.org/issue47256
#47253: LOAD_GLOBAL instruction with wrong source position
https://bugs.python.org/issue47253
#47252: socket.makefile documentation is missing data regarding the 'b
https://bugs.python.org/issue47252
#47251: Merge BINARY_SUBSCR_LIST_INT with BINARY_SUBSCR_LIST_TUPLE
https://bugs.python.org/issue47251
#47244: email.utils.formataddr does not respect double spaces
https://bugs.python.org/issue47244
#47242: Annoying white bar in IDLE (line 457 in sidebar.py)
https://bugs.python.org/issue47242
#47241: [C API] Move the PyCodeObject structure to the internal C API
https://bugs.python.org/issue47241
#47238: Python threading.Event().wait() depends on the system time
https://bugs.python.org/issue47238
#47236: Document types.CodeType.replace() changes about co_exceptionta
https://bugs.python.org/issue47236
#47228: Document that na??ve datetime objects represent local time
https://bugs.python.org/issue47228
#47222: subprocess.Popen() should allow capturing output and sending i
https://bugs.python.org/issue47222
#47219: asyncio with two interpreter instances
https://bugs.python.org/issue47219
#47218: adding name to lzmafile
https://bugs.python.org/issue47218
#47217: adding name to BZ2File
https://bugs.python.org/issue47217
Most recent 15 issues waiting for review (15)
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#47256: re: limit the maximum capturing group to 1,073,741,823, reduce
https://bugs.python.org/issue47256
#47255: Many broken :meth: roles in the docs
https://bugs.python.org/issue47255
#47254: enhanced dir?
https://bugs.python.org/issue47254
#47251: Merge BINARY_SUBSCR_LIST_INT with BINARY_SUBSCR_LIST_TUPLE
https://bugs.python.org/issue47251
#47243: Duplicate entry in 'Objects/unicodetype_db.h'
https://bugs.python.org/issue47243
#47233: show_caches option affects code positions reported by dis.get_
https://bugs.python.org/issue47233
#47222: subprocess.Popen() should allow capturing output and sending i
https://bugs.python.org/issue47222
#47218: adding name to lzmafile
https://bugs.python.org/issue47218
#47217: adding name to BZ2File
https://bugs.python.org/issue47217
#47216: adding mtime option to gzip open()
https://bugs.python.org/issue47216
#47215: Add "unstable" frame stack api
https://bugs.python.org/issue47215
#47208: Support libffi implementations that cannot support invocations
https://bugs.python.org/issue47208
#47205: posix.sched_{get|set}affinity(-1) no longer returns ProcessLoo
https://bugs.python.org/issue47205
#47200: Add ZipInfo.mode property
https://bugs.python.org/issue47200
#47199: multiprocessing: micro-optimize Connection.send_bytes() method
https://bugs.python.org/issue47199
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[Python-Dev] Re: Method __func__ objects are unpicklable
This is not just about the content of the name attributes: ;bound methods do contain a reference to the specific instance they are bound too - which is not retrievable (or maybe is through some dunder attribute) - this instance has to be pickled, transported and its reference updated on unpickling. On Fri, Jun 10, 2022 at 9:00 AM haael wrote: > > > During some sophisticated pickling I noticed that method `__func__` > objects are unpicklable, because they share the name with the bound > method object itself. > > > ``` > from pickle import dumps > > class A: > @classmethod > def b(cls): > pass > > print(A.b) # > > print(A.b.__func__) # > > dumps(A.b) # works > dumps(A.b.__func__) # breaks > # >Traceback (most recent call last): > # > File "", line 1, in > # >_pickle.PicklingError: Can't pickle : > # >it's not the same object as __main__.A.b > ``` > > > The last call compains that global symbol "A.b" is not the same object > as `A.b.__func__`. > > Everything would work if the `__func__` objects had the suffix > ".__func__" in their qualname. > > Actually setting the qualname of the `__func__` object makes it > picklable, but then the bound method object is unpicklable, as it > inherits the name from the `__func__`. It would be good if they were > separate. > > This is an attempt at emulating the desired behavior: > > > ``` > from pickle import dumps > > class A: > pass > > def c(cls): > pass > > A.c = lambda: c(A) > A.c.__qualname__ = "A.c" > A.c.__name__ = "c" > A.c.__self__ = A > A.c.__func__ = c > A.c.__func__.__qualname__ = "A.c.__func__" > > print(A.c) # > print(A.c.__func__) # > > dumps(A.c) # works > dumps(A.c.__func__) # works > ``` > > > Can we make the `__func__` objects picklable this way? > > > haael > > ___ > Python-Dev mailing list -- python-dev@python.org > To unsubscribe send an email to python-dev-le...@python.org > https://mail.python.org/mailman3/lists/python-dev.python.org/ > Message archived at > https://mail.python.org/archives/list/python-dev@python.org/message/N2J6MVLURTBAB5PJLJG3LO6U4PTPJMU2/ > Code of Conduct: http://python.org/psf/codeofconduct/ > ___ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/TZ4DCYPHB2B7U7HOMQG2C4AYVKS3KONI/ Code of Conduct: http://python.org/psf/codeofconduct/
[Python-Dev] Method __func__ objects are unpicklable
During some sophisticated pickling I noticed that method `__func__` objects are unpicklable, because they share the name with the bound method object itself. ``` from pickle import dumps class A: @classmethod def b(cls): pass print(A.b) # > print(A.b.__func__) # dumps(A.b) # works dumps(A.b.__func__) # breaks # >Traceback (most recent call last): # > File "", line 1, in # >_pickle.PicklingError: Can't pickle : # >it's not the same object as __main__.A.b ``` The last call compains that global symbol "A.b" is not the same object as `A.b.__func__`. Everything would work if the `__func__` objects had the suffix ".__func__" in their qualname. Actually setting the qualname of the `__func__` object makes it picklable, but then the bound method object is unpicklable, as it inherits the name from the `__func__`. It would be good if they were separate. This is an attempt at emulating the desired behavior: ``` from pickle import dumps class A: pass def c(cls): pass A.c = lambda: c(A) A.c.__qualname__ = "A.c" A.c.__name__ = "c" A.c.__self__ = A A.c.__func__ = c A.c.__func__.__qualname__ = "A.c.__func__" print(A.c) # print(A.c.__func__) # dumps(A.c) # works dumps(A.c.__func__) # works ``` Can we make the `__func__` objects picklable this way? haael ___ Python-Dev mailing list -- python-dev@python.org To unsubscribe send an email to python-dev-le...@python.org https://mail.python.org/mailman3/lists/python-dev.python.org/ Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/N2J6MVLURTBAB5PJLJG3LO6U4PTPJMU2/ Code of Conduct: http://python.org/psf/codeofconduct/
