# PR of feature: Mdst_vee2 info in b2bii conversion
### About work flow
1. Create JIRA tickets: (take BIIANA-143 as reference)
- Projects: Belle II Analysis
- Component: None
- assignee: me
- priority: Major
- description:
1. Add `Mdst_vee2::chisq()` info via `extraInfo` interface.
- `extraInfo(chiSquared)`, `extraInfo(ndf)=1`, `PValue`

- Where: around https://stash.desy.de/projects/B2/repos/software/browse/b2bii/modules/B2BIIMdstInput/src/B2BIIConvertMdstModule.cc#718
2. hits number and hits pattern variables associated with KS0 objects:
`hit_svd`, `nhits(3)`, `nhits(4)`

+ `nhits(3)`, `nhits(4)`: I think what I expect to do finally is implemented here! (the mask of the SVD hits) And what I use is followed the Belle standard: r-phi ≥ 1 hit, r-z ≥ 2 hits. But I still not comprehend the bit-shifting algo. here, and also how it can be access in the BASF2 steering script. I will try to understand this first.
2. Local repo:
I have cloned one in my KEKCC account. But I'm not quite sure how would the change be merged into the central branch. Below I just draft a bit my _imagination_, please correct me if I'm wrong, thanks:
- Create a new branch that based on **light-2002-janus**, by one of mentioned ways.
- Create PR branch from JIRA, it seems to me the branch name would be taken care automatically (?).
- `git checkout tags/light-2002-janus -b feature/XXX`
- After modification and testing, I'll have to commit and push the developing branch and ask to merge into **light-2002-janus**.
3. About BASF2 module:
- Compiling: do `scons` in `b2bii/modules/B2BIIMdstInput`
- Testing: Should I add a testing script to validate the variables of `Mdst_vee2` are corrected restored in BASF2 ntuple?
- Check syntax: `b2code-style-check`
- Change log: `b2bii/doc/whatsnew-since/release-04-01.txt`, `whatsnew.rst`
(in development/)
```bash
b2setup light-2002-janus
scons
```
(in my source code)
```python
from ctypes import cdll
cdll.LoadLibrary('/sw/belle/local/neurobayes-4.3.1/lib/libNeuroBayesCore_shared.so')
basf2.register_module('B2BIIConvertMdst',shared_lib_path='/gpfs/home/belle2/ycchen/development/modules/Linux_x86_64/opt/libB2BIIMdstInput.so')
```