### What problem does this PR solve?
Add get_txt function to reduce duplicate code
### Type of change
- [x] Refactoring
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Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>
### What problem does this PR solve?
### Type of change
- [ ] Bug Fix (non-breaking change which fixes an issue)
- [x] New Feature (non-breaking change which adds functionality)
### What problem does this PR solve?
add support for eml file parser
#1363
### Type of change
- [x] New Feature (non-breaking change which adds functionality)
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Co-authored-by: Zhedong Cen <cenzhedong2@126.com>
Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>
Zhichang Yu
Kevin Hu
yqkcn
黄腾