This is actually at least three problems:
- (arm*, mips*el) datetime issues, at least mostly inconsistency in
whether casting NaN to datetime gives NaT.
- (armel, armhf) SystemError in JSON processing. Known upstream as
https://github.com/pandas-dev/pandas/issues/14852 , but they don't have
a fix we're not already using.
- (mips, s390x, armel, armhf) Calling nose.SkipTest without importing
nose first. (This one happens in the existing deb_skip_* patches and
should be fixed by adding that import, but probably isn't worth fixing
without the others.)
