[Debian-science-sagemath] Sage broken with Python 2.7.13~rc1-1

[Tobias Hansen]

Hi all,

there was an update to python2.7 on Sunday that unfortunately broke
building or even running sage. The error one gets is this:

TypeError: sage.misc.fast_methods.WithEqualityById.__new__(UnknownClass)
is not safe, use object.__new__()

In the changelog it of python2.7 there is this entry:
Issue #5322: Fixed setting __new__ to a PyCFunction inside Python code.

leading to this bug report:
https://bugs.python.org/issue5322

I just found this, just wanted to let you know why nothing works.

Best,
Tobias