### What problem does this PR solve?

Add license statement.

### Type of change

- [x] Refactoring

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

### What problem does this PR solve?

Fix errors detected by Ruff

### Type of change

- [x] Refactoring

### What problem does this PR solve?

#2834 
### Type of change

- [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)

---------

Co-authored-by: Zhedong Cen <cenzhedong2@126.com>
Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>

### What problem does this PR solve?


### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

### What problem does this PR solve?

Add support for HTML file

### Type of change

- [x] New Feature (non-breaking change which adds functionality)