Made _logic a param
The _logic parameter is added in base.py to make this as small and
non-intrustive change.
Patch by: Sverre Rabbelier
# Please sort this file in alphabetical order by last (given) name.
# Please only include one name per line. If an (optional) email address is
# included, it must be RFC 2821 compliant (properly quoted, escaped, etc.).
# Lines beginning with # can be stripped from the file, as can blank lines.
"Todd Larsen" <tlarsen@google.com>
"Chen Lunpeng" <forever.clp@gmail.com>
"Sverre Rabbelier" <sverre@rabbelier.nl>
"Lennard de Rijk" <ljvderijk@gmail.com>,
"Pawel Solyga" <pawel.solyga@gmail.com>