doc: Fix Python example code.
* lang/python/doc/src/gpgme-python-howto.org: Fix chmod race. * lang/python/examples/howto/export-secret-key.py: Likewise. * lang/python/examples/howto/export-secret-keys.py: Likewise. * lang/python/examples/howto/temp-homedir-config.py: Likewise.
It's not for Python 2.7.
- GnuPG-bug-id: T6466
- Reported-by: Hanno Böck
- Co-authored-by: Ingo Klöcker
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>